1-(N-phenylaminoalkyl)piperazine derivatives substituted at position 2 of the phenyl ring

ABSTRACT

The present invention is directed to novel 1-(N-phenylaminoalkyl)piperazine derivatives substituted at the position 2 of the phenyl ring. Pharmaceutical compositions comprising the compounds of the invention also are contemplated. The compounds of the present invention also are contemplated for use in treating neuromuscular dysfunction of the lower urinary tract in a mammal.

This application is a continuation-in-part of Ser. No. 09/127,057, filed Jul. 31, 1998 which claimed priority under 35 U.S.C. §119 from U.S. Provisional Patent Application Ser. No. 60/070,268, filed Dec. 31, 1997 and Italian Patent Application No. MI97 001864 filed Aug. 1, 1997, all of which are incorporated by reference herein in their entirety.

FIELD OF THE INVENTION

This invention relates to 1-(N-phenylaminoalkyl)piperazine derivatives substituted at position 2 of the phenyl ring, to pharmaceutical compositions containing them and to uses for such derivatives and compositions.

BACKGROUND OF THE INVENTION

In mammals, micturition (urination) is a complex process that requires the integrated actions of the bladder, its internal and external sphincters, the musculature of the pelvic floor, and neurological control over these muscles at three levels (in the bladder wall or sphincter itself, in the autonomic centers of the spinal cord, and in the central nervous system at the level of the pontine micturition center (PMC) in the brainstem (pons) under the control of cerebral cortex) (De Groat, Neurobiology of Incontinence, (Ciba Foundation Symposium 151:27, 1990). Micturition results from contraction of the detrusor muscle, which consists of interlacing smooth muscle fibers under parasympathetic autonomic control from the sacral spinal cord. A simple voiding reflex is formed by sensory nerves for pain, temperature, and distension that run from the bladder to the sacral cord. However, sensory tracts from the bladder also reach the PMC, resulting in the generation of nerve impulses that normally suppress the sacral spinal reflex arc controlling bladder emptying. Thus, normal micturition is initiated by voluntary suppression of cortical inhibition of the reflex arc and by relaxation of the muscles of the pelvic floor and the external sphincter. Finally, the detrusor muscle contracts and voiding occurs.

Abnormalities of lower urinary tract function, e.g., dysuria, incontinence, and enuresis, are common in the general population. Dysuria includes urinary frequency, nocturia, and urgency, and may be caused by cystitis, prostatitis or benign prostatic hypertrophy (BPH) (which affects about 70% of elderly males), or by neurological disorders. Incontinence syndromes include stress incontinence, urgency incontinence, and overflow incontinence. Enuresis refers to the involuntary passage of urine at night or during sleep.

Prior to the work of the present inventors, treatment of neuromuscular dysfunction of the lower urinary tract has involved administration of compounds that act directly on the bladder muscles, such as flavoxate, a spasmolytic drug (Ruffman, J. Int.Med.Res. 16:317, 1988) also active on the PMC (Guarneri et al., Drugs of Today 30:91, 1994), or anticholinergic compounds such as oxybutynin (Andersson, Drugs 35:477, 1988). The use of α₁-adrenergic receptor antagonists for the treatment of BPH is also common but is based on a different mechanism of action. (Lepor, Urology, 42:483, 1993).

However, treatments that involve direct inhibition of the pelvic musculature (including the detrusor muscle) may have unwanted side effects such as incomplete voiding or accommodation paralysis, tachycardia and dry mouth (Andersson, Drugs 35;477, 1988). Thus, it would be advantageous if compounds were available that act via the peripheral or central nervous system to, for example, affect the sacral spinal reflex arc and/or the PMC inhibition pathways in a manner that restores normal functioning of the micturition mechanism.

1-(N-phenyl-N-cyclohexylcarbonyl-2-aminoethyl)-4-(2-methoxyphenyl)piperazine (compound A)

is described in GB 2 263110 A and is reported to be a 5-HT_(1A) receptor antagonist. It is also disclosed that it can be used for the treatment of central nervous system disorders, for example as an anxiolytic agent in the treatment of anxiety.

The compounds of the present invention, described below, are structurally different from compound A because of the novel substituents present on the aniline ring at the 2 position. Other differences between the compounds of the present invention and those disclosed in GB 2 263110 A are the substitutions on the aromatic ring at position 4 of the piperazine ring. These structural variations are neither disclosed nor suggested by GB 2 263110 A, particularly with regard to compounds that can be used to improve urinary tract function. These structural variations result in compounds that are more potent than compound A in pharmacological tests predictive of activity on the lower urinary tract, in particular for activity against urinary incontinence.

Other compounds which have been found by the present inventors to be useful in the methods of the present invention, e.g., treatment of disorders of the urinary tract, are disclosed in U.S. Pat. No. 4,205,173; EP 711,757; DE patent 2,405,441; Chem. Pharm. Bull. 33:1823-1835 (1985), and J. Med. Chem. 7:721-725 (1964), all of which are incorporated by reference.

SUMMARY OF THE INVENTION

In one aspect the invention is directed to compounds of formula I:

wherein

R is hydrogen

R₁ is chosen from the group consisting of hydrogen and lower alkyl;

R₂ is chosen from the group consisting of alkoxy, phenoxy, nitro, cyano, acyl, amino, acylamino, alkylsulphonylamino, alkoxycarbonyl, N-acylaminocarbonyl, N-alkylaminocarbonyl, N,N-dialkylaminocarbonyl, aminocarbonyl, halo, trifluoromethyl or polyfluroalkoxy group,

n=1or 2;

B is chosen from the group consisting of optionally substituted aryl, optionally substituted bicyclic aryl group, optionally substituted 9-member bicyclic heteroaromatic containing one heteroatom, and an optionally substituted benzyl group,

with the proviso that if B is aryl and is substituted by an alkoxy group, the alkoxy group must be at the two position, and

if R₁ is hydrogen and R₂ is a nitro group and n=1, then B cannot be a phenyl, 2methoxyphenyl 4-chlorophenyl, 3 acetylphenyl, 3,4,5 trimethoxyphenyl, 2-chloro-4-methylphenyl or 2-pyridyl group; and

if R and R₁ are hydrogen and B is optionally substituted phenyl, then R₂ cannot be acyl, acylamino, alkoxycarbonyl, N-acylaminocarbonyl, N-alkylaminocarbonyl, N,N-dialkylaminocarbonyl,

and enantiomers N-oxides hydrates and pharmaceutically acceptable salts thereof.

Preferred is when n=1. Further preferred is when B is optionally substituted phenyl. Further preferred is when B is indolyl.

Also preferred is when R₁ is hydrogen; R₂ is chosen from the group consisting of alkoxy, phenoxy, nitro, cyano, amino, halo, trifluoromethyl or polyfluroalkoxy; n=1; and B is substituted phenyl.

Also preferred is when R₁ is hydrogen; R₂ is chosen from the group consisting of alkoxy, phenoxy, nitro, cyano, amino, halo, trifluoromethyl or polyfluroalkoxy; n=1; and B is indolyl.

Also preferred is when R₁ is hydrogen; R2 is chosen from the group consisting of alkoxy, nitro, halo, trifluoromethyl or polyfluroalkoxy; n=1, and B is substituted phenyl.

Also preferred is when R₁ is hydrogen; R₂ is chosen from the group consisting of alkoxy, nitro, halo, trifluoromethyl or polyfluroalkoxy; n=1; and B is substituted indolyl.

In another aspect, the invention is directed to compounds chosen from the group consisting of List I A:

1-[N-cyclohexylcarbonyl-N-(2-methanesulphonylaminophenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-methoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-benzyloxycarbonylpheny)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine;

1-[N-(2-nitrophenyl)-N-(2-pyrazinecarbonyl)-2-aminoethyl)]-4-(4-indolyl)piperazine,

1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-amino-2-methoxyphenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-acetylamino-2-methoxyphenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-trifluoroacetylamino-2-methoxyphenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-propoxycarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-(N-acetyl-N-cyclohexylcarbonyl)amino-2-methoxyphenyl]piperazine;

1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-(bis-cyclohexylcarbonyl)amino-2-methoxyphenyl]piperazine,

1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-cyclohexanecarbonylamino-2-methoxyphenyl)piperazine,

1-[N-(2-nitrophenyl)-N-(2-pyrimidinecarbonyl)-2-aminoethyl)]-4-(2-methoxyphenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(2-methoxy-4-nitrophenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(4-amino-2-methoxyphenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(4-acetylamino-2-methoxyphenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl]-4-(4-indolyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl)]-4-(4-acetylamino-2-methoxyphenyl)piperazine,

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-trifluoromethoxyphenyl)piperazine;

1-[N-(2-nitrophenyl)-N-(5-thiazolylcarbonyl)-2-aminoethyl)]-4-(2-methoxyphenyl)piperazine,

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-bromo-5-methoxybenzyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-iodophenyl)-2-aminoethyl 1-4-(4-indolyl)piperazine,

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-trifluoromethoxyphenyl)piperazine;

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine;

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-amino-2-methoxyphenyl)piperazine,

1-[N-(2-cyanophenyl)-N-cyclohexylcarbony-2-aminoethyl]-4-(4-acetylamino-2-methoxyphenyl)piperazine;

1-[N-(2-acetylphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine;

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-indolyl)piperazine;

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-bromo-5-methoxybenzyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(1-cyclohexylcarbonyl-4-indolyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl )-2-aminoethyl ]-4-(4-amino-2-cyanophenyl)piperazine;

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl )-2-aminoethyl]-4-(2-cyanophenyl)piperazine;

1-[N-cyclohexylcarbony-N-(2-methanesulphonylaminophenyl)-2-aminoethyl] -4-(4-indolyl)piperazine; and

1-[N-cyclohexylcarbonyl-N-(2-methoxyphenyl)-2-aminoethyll-4-(1-cyclohexylcarbonyl-4-indolyl)piperazine,

and pharmaceutically acceptable salts thereof.

In yet another aspect, the invention is directed to compounds of formula IB

wherein

R is a hydrogen atom, an alkylcarbonyl, a cycloalkylcarbonyl, a substituted cycloalkylcarbonyl or a monocyclic heteroarylcarbonyl group,

n=1 or 2;

R₁ is a hydrogen atom or a lower alkyl group,

R₂ is an alkoxy, phenoxy, nitro, cyano, acyl, amino, acylamino, alkylsulphonylamino, alkoxycarbonyl, aminocarbonyl, N-alkylaminocarbonyl, N,N-dialkylaminocarbonyl, N-acylaminocarbonyl, halo, trifluoromethyl or polyfluoroalkoxy group; and

B is a bicyclic heteroaromatic with the proviso that B is not a 9-member bicyclic heteroaromatic containing one heteroatom.

Preferred is when R is chosen from the group consisting of hydrogen and cycloalkylcarbonyl; R₁ is hydrogen; R₂ is chosen from the group consisting of alkoxy, phenoxy, nitro, cyano, acyl, amino, acylamino, alkylsulphonylamino, alkoxycarbonyl, aminocarbonyl, N-alkylaminocarbonyl, N,N-dialkylaminocarbonyl, N-acylaminocarbonyl, halo, trifluromethyl or polyfluroalkoxy group n=1, and B is a 10-member bicyclic heteroaromatic containing one heteroatom.

Further preferred is when n=1.

Further preferred is when B is a 10-member bicyclic heteroaromatic containing one heteroatom.

Further preferred is when B is an optionally substituted quinolyl.

The invention also includes the enantiomers, diastereomers, N-oxides, crystalline forms, hydrates and pharmaceutically acceptable salts of compounds of the formula 1 and 1B and the list 1A, as well as metabolites of these compounds having the same type of activity (hereafter sometimes referred to as “active metabolites”).

As used herein with reference to variable R, alkylcarbonyl radicals include C₁-C₆ alkylcarbonyl, cycloalkylcarbonyl includes cyclohexylcarbonyl, substituted cycloalkylcarbonyl includes cyclohexylcarbony substituted with alkyl or aryl groups and monocyclic heteroaryl radicals include monocyclic aromatic radicals of 5 to 7 ring atoms containing one or more hetero atoms (e.g., oxygen, nitrogen, and sulfur). Monocyclic heteroarylcarbonyl has the same definition as monocyclic heteroaryl, but also comprises a carbonyl group linked to a carbon atom of the ring.

As used herein with reference to variable B, a mono or bicyclic aryl radical means an aromatic radical having 6 to 12 carbon atoms (e.g., phenyl or naphthyl) which is substituted by one or more substitutents. Preferred substitutents for aryl radicals are lower alkyl, lower alkoxy (e.g., methoxy, ethoxy, propoxy, and butoxy), lower haloalkoxy (e.g., 2,2,2-trifluoroethoxy) halogen, amino, acylamino, alkylsulfonylamino, and (lower) alkylamino substituents.

As used with respect to variable B, monocyclic heteroaryl radical has the same meaning as for R, above, and bicyclic heteroaryl radical means a bicyclic aromatic radical containing one or more heteroatoms (e.g., nitrogen, oxygen, sulfur) and 9 to 12 ring atoms. Benzyl radicals, with respect to variable B, include phenylmethyl radicals which may be optionally substituted by one or more substituents. Preferred substituents for the benzyl radicals are alkyl, alkoxy, halogen, nitro, cyano, amido, amino, alkylamino, acylamino, alkylsulphonylamino or acyl substituents. Preferred substituents at B are optionally substituted monocyclic aryl and bicyclic heteroaryl. Most preferred substituents at B are alkoxyphenyl and mononitrogen-containing bicyclic heteroaryl.

Preferred substituents at R₁ are hydrogen and methyl.

Preferred substituents at R₂ are nitro, cyano, acyl, and aminocarbonyl. Most preferred at R₂ is nitro. A preferred value for n is 1.

Preferred substituents for B are optionally substituted phenyl and indolyl.

The invention further provides pharmaceutical compositions comprising a compound of formula I, a specific compound from List 1A, or a compound of formula 1B, or an enantiomer, diastereomer, N-oxide, crystalline form, hydrate or pharmaceutically acceptable salt of the compound, in admixture with a pharmaceutically acceptable diluent or carrier.

In another aspect, the present invention is directed to methods for reducing the frequency of bladder contractions due to bladder distension by administering one or more selected compounds of Formula I, a specific compound from List 1A, or a compound of formula 1B, to a mammal (including a human) in need of such treatment, in an amount or amounts effective for the particular use.

In a further aspect, the present invention is directed to methods for treating disorders of the urinary tract in a subject in need of such treatment, comprising administering an effective amount of a compound of Formula 1, a specific compound from List 1A, or a compound of formula 1B, to ameliorate at least one of urinary urgency, increased urinary frequency, incontinence, urine leakage, enuresis, dysuria, urinary hesitancy, and difficulty in emptying bladder.

In yet another aspect, the invention is directed to methods for blocking 5-HT_(1A) serotonergic receptors, and, by virtue of this inhibitory activity, to methods for the treatment of CNS disorders due to serotonergic dysfunction such as anxiety, depression, hypertension, sleep/wake cycle disorders, feeding behavior, sexual function and cognition disorders in mammals, particularly in humans, by delivering to the environment of the 5-HT_(1A) serotonergic receptors, e.g., to the extracellular medium (or by administering to a mammal possessing such receptors) an effective amount of a compound of formula 1, list 1A, for formula 1B (hereinafter “compounds of the invention”).

DETAILED DESCRIPTION OF THE INVENTION

All patents, patent applications, and literature references cited in the specification are hereby incorporated by reference in their entirety. In the case of inconsistencies, the present disclosure, including definitions, will prevail.

The activity of the compounds of the invention as inhibitors of frequency of micturition renders them useful for the treatment of neuromuscular dysfunctions of the lower urinary tract in mammals, including without limitation dysuria, incontinence and enuresis. Surprisingly, the introduction of selected substituents at position 2 of the aniline ring in compounds of Formula I, Formula IB and List IA confers upon these compounds a distinctly higher potency with regard to compound A and also to the isomers bearing the same substituent at position 3 or 4. This information was obtained by testing compound A and the corresponding 2, 3 and 4 nitroaniline derivatives (Example 2 and compounds B and C) in a rat model. The rhythmic contraction of rat bladders was induced by filling the bladders with a physiologic solution. The effect of test compounds of the invention on the frequency and amplitude of the contractions was evaluated. Of particular interest is the time of disappearance of induced contractions. (ED_(10 min) in Table 1, below).

Data in Table 1(in particular, ED₅₀ (frequency)) show that the 2-substituted compounds of the invention are clearly more potent inhibitors of the frequency of urinary bladder contractions.

The effect of the drugs currently available for administration to humans for treatment of neuromuscular function of the lower urinary tract (flavoxate and oxybutynin) on the above-described rat model is also shown, for comparative purposes, in Table 1.

The compounds of the invention are more potent and acted for a longer period of time (as measured by duration of bladder quiescence with no contractions) than did compounds A, flavoxate, and oxybutynin. Moreover, in contrast to oxybutynin, the compounds of the invention did not affect the amplitude of the contractions (no effect on ED₅₀ (amplitude) in Table 1), suggesting no impairment of bladder contractility that could result in residual urine being left in the bladder after micturition.

In addition, the beneficial effect on the lower urinary tract of the compounds of the invention has been shown in a cystometry model in conscious rats, where the compounds of the invention are also superior to compound A and the reference drugs. In fact, compounds of the invention increased the bladder capacity at doses lower than compound A and flavoxate (oxybutynin does not affect bladder capacity) (Table 2). Furthermore, in contrast to the effects of oxybutynin, no impairment of bladder contractility (decrease in MP) was observed.

Finally, the compounds of the invention have a high and selective affinity for the 5-HT_(1A). receptor, an affinity and selectivity displayed to a much lesser extent by compound A, (Table 3). The compounds of the invention have also been shown to antagonize both pre- and post-synaptic 5-HT_(1A) receptors much more potently than compound A (Table 4), strongly suggesting a role for the 5-HT_(1A) receptor in the action of the compounds of the invention.

Subjects who can benefit from administration of the compounds and compositions of the invention include humans who are affected by neuromuscular dysfunction of the lower urinary tract, described by E. J. McGuire in “Campbell's UROLOGY” 5^(th) Ed. 616-638, 1986, W. B. Saunders Company, and also include patients affected by any physiological dysfunction related to impairment of 5-HT_(1A) receptor function. Such dysfunctions include, without limitation, central nervous system disorders such as depression, anxiety, eating disorders, sexual dysfunction, addiction, and related problems.

The present invention encompasses pharmaceutical formulations comprising the compounds disclosed above, as well as methods employing these formulations for treating neuromuscular dysfunction of the lower urinary tract such as dysuria, incontinence, enuresis, and the like. Dysuria includes urinary frequency, nocturia, urgency, and difficulty in emptying the bladder, i.e., a suboptimal volume of urine is expelled during micturition.

Incontinence syndromes include stress incontinence, urgency incontinence, and overflow incontinence. Enuresis refers to the involuntary passage of urine at night or during sleep.

Without wishing to be bound by theory, it is believed that administration of the 5-HT_(1A) receptor antagonists of the invention prevents unwanted activity of the sacral reflex arc and/or cortical mechanisms that control micturition. Thus it is contemplated that a wide range of neuromuscular dysfunctions of the lower urinary tract can be treated using the compounds of the present invention.

An “effective amount” of the compound for treating a urinary disorder is an amount that results in measurable amelioration of at least one symptom or parameter of the disorders described above.

An effective amount for treating the disorder can easily be determined by empirical methods known to those of ordinary skill in the art, such as by establishing a matrix of dosages and frequencies of administration and comparing a group of experimental units or subjects to each point in the matrix. The exact amount to be administered to a patient will vary depending on the state and severity of the disorder and the physical condition of the patient. A measurable amelioration of any symptom or parameter can be determined by a physician skilled in the art or reported by the patient to the physician. It will be understood that any clinically or statistically significant attenuation or amelioration of any symptom or parameter of urinary tract disorders is within the scope of the invention. Clinically significant attenuation or amelioration means perceptible to the patient and/or to the physician.

For example, a single patient may suffer from several symptoms of dysuria simultaneously, such as, for example, urgency and excessive frequency of urination, either or both of which may be reduced using the methods of the present invention. In the case of incontinence, any reduction in the frequency or volume of unwanted passage of urine is considered a beneficial effect of the present methods of treatment.

The compounds of the present invention may be formulated into liquid dosage forms with a physiologically acceptable carrier, such as, for example, phosphate buffered saline or deionized water. The pharmaceutical formulation may also contain excipients, including preservatives and stabilizers, that are well-known in the art. The compounds can be formulated into solid oral or non-oral dosage units such as, for example, tablets, capsules, powders, and suppositories, and may additionally include excipients, including without limitation lubricant(s), plasticizer(s), colorant(s), absorption enhancer(s), bactericide(s), and the like.

Modes of administration include oral and enteral, intravenous, intramuscular, subcutaneous, transdermal, transmucosal (including rectal and buccal), and by-inhalation routes. Preferably, an oral or transdermal route is used (i.e., via solid or liquid oral formulations, or skin patches, respectively).

The amount of the agent to be administered can range from between about 0.01 and about 25 mg/kg/day, preferably from between about 0.1 and about 10 mg/kg/day and most preferably from between about 0.2 and about 5 mg/kg/day. It will be understood that the single pharmaceutical formulations of the present invention need not contain the entire amount of the agent that is effective in treating the disorder, as such effective amounts can be reached by administration of a plurality of doses of such pharmaceutical formulations.

In a preferred embodiment of the present invention, compounds are formulated in capsules or tablets, each preferably containing 50-200 mg of the compounds of the invention, and are most preferably administered to a patient at a total daily dose of 50-400 mg, preferably 150-250 mg, and most preferably about 200 mg for relief of urinary incontinence and dysfunctions amenable to treatment with 5-HT_(1A) receptor ligands.

The methods, tables and examples provided below are intended to more fully describe preferred embodiments of the invention and to demonstrate its advantages and applicability, without in any way limiting the scope of the invention.

SYNTHESIS OF THE COMPOUNDS OF THE INVENTION

The compounds of the invention may be prepared by the methods illustrated in the following reaction schemes, or by modifications thereof, using readily available starting materials, reagents and conventional synthesis procedures well known to those of ordinary skill in the art.

Unless otherwise specified, the substituents of the compounds and intermediates present in the reaction schemes are defined in the same manner as they are defined above in formula I, formula IB is and list IA. One method to synthesize compounds of formula I and formula IB (R=H) and formula IB and list IA (R=H) is depicted in Scheme 1.

Ortho-substituted anilines of formula II (Y=NH₂) are alkylated with 1,ω-disubstituted alkanes (Z) to give product III. The reaction is carried out in an inert organic solvent, preferentially a polar aprotic solvent such as N,N-dimethylformamide (DMF), dimethylsulfoxide (DMSO), dioxane, tetrahydrofuran (THF), acetone, acetonitrile or

chlorinated solvents such as dichloromethane, chloroform, 1,2-dichloroethane or a protic solvent such as n-butanol (n-BuOH). The reactions are generally performed at a temperature between 0° C. and +120° C., in the presence of a proton acceptor such as triethylamine (Et₃N), diisopropylethylamine, or the like, and optionally in the presence of potassium iodide.

In compounds of formula Z, X and X₁ can be Cl, Br, I aryl, or alkylsulfonyloxy groups.

Intermediates of formula III are used in the alkylation of suitable piperazine derivatives IV to give the compounds of formula I and IB (where R=H).

These alkylations may be carried out in a chlorinated solvent such as dichlorometane, chloroform or 1,2-dichloroethane, or in a polar aprotic solvent such as DMF, THF, acetone, acetonitrile, or in a polar protic solvent such as n-BuOH, etc., or in an a polar solvent such as toluene, benzene, it-heptane, etc., at a temperature between 0° C. and 120° C., optionally in the presence of a proton acceptor, such as Et₃N, 4-dimethylaminopyridine, potassium carbonate, cesium carbonate, and the like, and optionally in the presence of potassium iodide.

Piperazines of formula IV which are not commercially available may be prepared by reaction of the suitable B-NH₂ derivatives (which generally may be easily obtained by reduction of the corresponding B—NO₂ derivatives) with bis-(2-chloroethyl)amine or bis-(2-hydroxyethyl)amine in presence of excess hydrogen chloride. These reactions can be performed in aprotic solvents such as dimethylformamide, diglyme or toluene at a temperature between +40° C. and the reflux temperature of the solvent, generally in the presence of a base such as potassium carbonate, cesium carbonate, or the like, and optionally in the presence of potassium iodide.

Compounds of formula V can be conveniently prepared starting from compounds V in which X is a COO-lower alkyl group and n is n-1. Conventional reduction procedures (e.g., use of lithium aluminum hydride or other metal complex hydrides) afford the corresponding compounds V in which X is CH₂OH and n is n-1, which can be in turn conventionally converted into compounds of formula V in which X is a leaving group as described above The starting esters can be prepared by well known Michael reactions or by the nucleophilic displacement reaction of a monosubstituted piperazine on the appropriate 2,3-unsaturated ester or 2-haloester.

Alternative procedures to obtain compounds of formula V consists in alkylating the appropriate monosubstituted piperazine derivatives with a compound with the formula X—CH(R₁)(CH₂)_(n)−1CH₂—OPrG or X—(CH₂)_(n)CH(R₁)—X where X is a leaving group and n has the same meaning as above, and PrG is a protecting group (e.g. O-tetrahydropyranyl), which can be removed after alkylation of the piperazine.

Another approach to synthesize intermediate compounds of formula III utilizes starting materials with structure II (Y=halogen). These starting materials are reacted with compounds of formula Z in which X and X₁are, respectively, NH₂ and OH. These alkylation reactions are carried out in an aprotic solvent such as DMF, toluene, or in a polar protic solvent such as i7-BuOH, etc., at a temperature between +40° C. and +140° C., in general using one equivalent or excess of a reagent of formula Z (X=NH₂) as a proton acceptor, as described by G. Doleschall et al., Tetrahedron, 32, 57-64 (1976). The resulting aminoalcohols of formula III (X₁=OH) are reacted with a chlorinating agent such as POCl₃, SOCl₂ or PCl₅ to give the intermediates, also of formula III (X₁=Cl), or with an alkyl or arylsulfonyl chloride to give the corresponding sulfonyl esters. These reactions are carried out in an aprotic solvent such as chloroform, DMF, pyridine, and the like at a temperature between +50° C. and the reflux temperature of the solvent.

Compounds of formula I and IB (R=H) may also be obtained by alkylation of compounds of formula II (Y=NH₂) with intermediates of formula V, in which B, R₁ and n have the same meanings as above and X is a halogen atom such as chlorine or bromine, or a leaving group such as methanesulfonyloxy or p-toluenesulfonyloxy groups.

These reactions may be carried out without solvent or in an aprotic solvent such as dichloromethane, chloroform, DMF, TUF, acetone, acetonitrile or in a protic solvent such as n-butanol, etc. at a temperature between 0° C. and +160° C., optionally in the presence of a proton acceptor, such as Et₃N, potassium carbonate, cesium carbonate, 4-dimethylaminopyridine and the like, and optionally in the presence of potassium iodide.

Compounds of formula I and IB where R₂ is CN can be also obtained from the compounds of formula I and IB in which R₂ is CONH₂ by dehydration reactions. P₂O₅, PCl₅, Ph₃P, and the like may be used as dehydrating agents (J. March, Advanced Organic Chemistry, IV Ed., page 1041, Wiley Interscience, 1992). Dehydration reactions may be carried out in a chlorinated solvent such as dichloromethane, chloroform, carbon tetrachloride or in an aprotic solvent such as DMF, toluene, etc. at a temperature between +40° C. and the reflux temperature of the solvent, optionally in the presence of a base such as Et₃N.

Alternatively,compounds of formula I and IB (R=H) may be obtained by arylation of intermediates of formula V (X=NH₂) with a starting material of formula II (Y=Cl, Br, F, I or trifluoromethanesulphonyloxy). These reactions may be carried out using the same solvents and conditions as described above or by employing palladium complex catalysis (Synlett,p.329 (1996)).

Compounds of formula I and IB in which R₂ is COalk can be synthesized from compounds I in which R₂ is H by an acylation reaction that can be carried out using boron trichloride as a Lewis acid and acetonitrile as a reagent in an aprotic solvent such as chloroform, 1,2-dichloroethane, toluene, etc. at temperatures between 0° C. and 100° C., followed by acidic hydrolysis by treatment with HCl at 100° C., (T. Sugasawa et al., Chem. Pharm. Bull., 33, 1826-1835 (1985)).

Compounds of formula I and IB (R=H) are acylated to give compound IB (R other than H) by reaction with an appropriate acyl halide R′Hal in which R′ represents an alkylcarbonyl, cycloalkylcarbonyl or monocyclic heteroarylcarbonyl group and Hal represents a halogen atom. The reaction can be performed in aprotic solvents such as dichloromethane, chloroform, 1,2-dichloroethane, DMF, acetone, acetonitrile, toluene, etc., at temperatures between 0° C. and 100° C., optionally in the presence of an organic base as a proton acceptor such as Et₃N, diisopropylethylamine (DIPEA), 4-dimethylaminopyridine, and the like.

Alternatively,compounds with formula IB (i.e, where R₂=Br, I, OSO₂F or OSO₂CF₃) in which R is as defined above, but is not hydrogen, may be used to synthesize compounds of formula I in which R₂ is CN, CONH₂, COCH₃ or COOCH₃ by reaction of reagents such as trimethylsilyl isocyanate and t-butyl lithium (J. Org. Chem. 55, 3114 (1990)), lithium cyanide and tetrakis(triphenylphosphine)palladium(0) (EP711757), carbon monoxide-methanol and palladium diacetate in the presence of 1,3-diphenylphosphinopropane (J. Org. Chem. 59, 6683 (1994)). Such reactions may be carried out in polar or a polar solvent such as THF, toluene, benzene, DMSO, and the like.

Another method to synthesize compounds of formula I and IB in which R₁ is H is depicted in Scheme 2, below.

Ortho-substituted halobenzenes of formula II (Y=halo) are used to arylate protected aminoalkylaldehydes of formula VII (X=NH₂) to give the corresponding protected arylaminoalkylaldehydes VIII. The reaction may be carried out in an aprotic solvent such as pyridine, DMF, toluene, or the like at a temperature between +40° C. and 120° C., optionally in the presence of a base such as Et₃N or employing palladium complex catalysts as above.

Another route for the preparation of intermediates of formula VIII consists in alkylating compounds of formula II (Y=NH₂) with protected reactive compounds of formula VII (X=halo) by conventional procedures known to those skilled in the art. Compounds with formula VIII are stable and are deprotected by standard methods just before their use in the following steps.

Aldehydes of formula VIII′, obtained from deprotection of compounds with formula VIII, may be reacted without isolation with N-substituted piperazines IV under reductive conditions to give compounds of formula I and IB (R=R₁=H). These reactions may be carried out in polar solvents such as methanol, ethanol or in chlorinated solvents, such as dichloromethane, chloroform, and the like, using alkali borohydrides such as NaBH₄ and NaBH₃CN, NaBH(OAc)₃ or using borane complexes such as BH₃-Py, optionally in the presence of acidic promoter, such as acetic acid, at temperatures between +10° C. and 100° C.

Alternatively, intermediates of formula VIII may be acylated with R′Hal to give compounds of formula IX using the same conditions as described above.

Intermediates of formula IX are deprotected by well-known methods just before their use in the final step to give the corresponding aldehydes (IX′), which may be reacted with appropriate N-substituted piperazines of formula IV using alkali borohydrides such as NaBH₄, NaBH₃CN or NaBH(OAc)₃, optionally in the presence of catalytic amounts of acetic acid, or of a titanium catalyst such as titanium tetraisopropoxide, yielding compounds of formula I. These reactions may be carried out in chlorinated solvents such as dichloromethane or chloroform, or in polar aprotic solvents such as methanol or ethanol at temperatures between +10° C. and +100° C.

An alternative procedure to afford compounds of formula I, IB and list IA (Scheme 3), where R₂ is an electron withdrawing group (i.e. NO₂, CN, I) consists of acylating by conventional procedure with R′-Hal (R′=alkylcarbonyl) the proper aniline (II, Y=NH₂) to obtain compounds X, which in turn can be alkylated with compounds V where X is a leaving group. The alkylation of compound X can be carried out by preforming the aza-anion of X through the use of bases (e.g. potassium tert-butoxide, NaNH₂, Na, NaH, buthyl lithium or other lithium bases, NaOH/KOH by phase transfer catalysis) in a solvent such as toluene, dimethylsulfoxide, DMF, acetonitrile, acetone, diethyl ether, dioxane, tetrahydrofurane at a temperature included in the range between −25° C. and the temperature of reflux of the solvent. The following alkylation to afford compounds I and IB can be performed by adding to the reaction mixture the compounds V in the same reaction condition as above.

The same alkylation reaction of compounds X can be carried out using compound VII as an alternative methods to prepare compounds IX.

The compounds of formula IB and list IA (R=alkylcarbonyl, R₂=alkylCO) can be prepared from the proper compounds X (R₂=alkylCO) by protecting the keto group (e.g. as 1,3-dioxolanyl derivatives) by standard procedures, then by alkylating the nitrogen of the amido group as described above. Subsequent deprotection affords the desired compounds IB.

In addition, compounds of formula I where R is alkylcarbonyl, cycloalkylcarbonyl or monocyclic heteroarylcarbonyl group could also be synthesized using this methodology.

Compound AA

1-(N-phenyl-2-aminoethyl)-4-(2-methoxyphenyl)piperazine

Compounds B and D

1-[N-(3-nitrophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxypheny)piperazine (Compound B) and 1-[N-(3-nitrophenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine (Compound D)

Compounds C and E

1-[N-(4-nitrophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine (Compound C) and 1-[N-(4-nitrophenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine (Compound E)

EXAMPLE 1

1-[N-(2-nitrophenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

A mixture of 3.03 g of 2-chloronitrobenzene, 4.52 g of 1-(2-aminoethyl)-4-(2-methoxyphenyl)piperazine, and 3.18 g of anhydrous potassium carbonate in 30 mL of n-butanol was stirred for 32 h at reflux. After cooling, the mixture was poured into H₂O, then extracted with EtOAc and the organic phase dried on Na₂SO₄. The crude obtained by evaporating the solvent was purified by flash chromatography (EtOAc-petrolium ether 4:6) and the residue obtained after evaporation of the solvents was taken up with Et₂O, stirred and filtered giving 2.2 g (31%) of the title compound. Melting point: 117-118° C.

¹H-NMR (CDCl₃, δ): 8.50 (bs, 1H, NH), 8.19 (d, 1H, aniline H3), 7.45 (dd, 1H, aniline H5), 7.08-6.78 (m, 5H, aniline H6 and methoxyphenyl ring CHs), 6.63 (dd, 1H, aniline H4), 3.86 (s, 3H, OCH₃), 3.40 (dt, 2H, NHCH ₂CH₂), 3.27-3.04 (m, 4H, piperazine protons), 2.80-2.62 (m, 6H, NHCH₂ CH ₂ and piperazine protons).

EXAMPLE 2

1-[N-(2-nitrophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl) piperazine

Cyclohexanecarbonyl chloride (0.98 mL) and triethylamine (1.03 mL) were added in sequence to a solution containing 2.1 g of the compound described in example 1 and 15 mL of 1,2-dichloroethane. The mixture was stirred for 16 h at reflux. Finally it was cooled, diluted with CHCl₃, washed with NaOH 1 N and H₂O. The organic phase was dried on anhydrous Na₂SO₄ and the crude obtained after evaporation of the solvents was purified via flash chromatography (EtOAc-petrolium ether 1:1) and subsequently crystallized from cyclohexane giving 1.79 g (65%) of the title compound. Melting point: 119-121° C.

¹H-NMR (CDCl₃, δ): 8.04 (d, 1H, nitrophenyl ring H3), 7.65-7.47 (m, 3H, nitrophenyl ring H4,5,6), 7.10-6.75 (m, 4H, methoxyphenyl ring CHs), 4.15-3.92 (m, 1H, C(O)NCH(H)CH₂), 3.83 (s, 3H, OCH₃), 3.70-3.50 (m, 1H, C(O)NCH(H)CH₂), 3.10-2.80 (m, 4H piperazine protons), 2.80-2.40 (m, 6H, piperazine protons and C(O)NCH₂CH ₂), 2.10-0.75 (m, 11H, cyclohexyl protons).

By conventional methods, the following salts of compound of Example 2 were prepared:

monohydrochloride, m.p. 183-187° C. (Me₂CO-Et₂O);

monomethanesulphonate, m.p. 150-153° C. (Me₂CO);

monomethanesulphonate hydrate, m.p. 136-140° C.

EXAMPLE 3

1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

A solution of 2.09 g of 2-trifluoromethoxyaniline and 3.15 g of 1-(2-chloroethyl)-4-(2-methoxyphenyl)piperazine in 20 mL of n-butanol was stirred at 100° C. for 2 hrs. The mixture was then cooled, diluted with H₂O alkalinized with 2 N NaOH and extracted with CHCl₃. The organic phase was dried on anhydrous Na₂SO₄, evaporated until dry and the crude purified via flash chromatography (EtOAc-petrolium ether 3:7) and subsequently crystallized from EtOH giving 0.55 g (12%) of the title compound. Melting point: 69.5-71° C.

¹H-NMR (CDCl₃, δ): 8.02-7.85 (br, 1H, NH), 7.43-7.27 (m, 2H, aniline CHs), 7.03-6.80 (m, 4H, methoxyphenyl ring CHs), 6.72 (dd, 1H aniline CH), 6.57 (t, 1H, aniline CH), 3.86 (s, 3H, OCH₃), 3.43-3.23 (m, 2H, NHCH ₂CH₂), 3.23-3.03 (m, 4H, piperazine protons), 2.85-2.60 (m, 6H, piperazine protons and NHCH₂CH ₂).

EXAMPLE 4

1-[N-(2-trifluoromethoxyphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 2, except that the compound in example 3 was used in place of the compound in example 1 (i.e. 4-dimethylaminopyridine replaced triethylamine) and heated for 1.5 h at reflux. The raw material was purified via flash chromatography (EtOAc-petrolium ether 4:6). Yield: 44%.

¹H-NMR (CDCl₃, δ): 7.48-7.25 (m, 4H, trifluoromethoxyaniline ring CHs), 7.02-6.81 (m, 4H, methoxyphenyl ring CHs), 4.40-4.20 (m, 1H, C(O)NCHHCH₂), 3.84 (s, 3H, OCH₃), 3.36-3.18 (m, 1H, C(O)NCHHCH₂), 3.10-2.90 (m, 4H, piperazine protons), 2.75-2.45 (m, 6H, piperazine protons and C(O)NCH₂CH ₂), and 2.03-1.80 (m, 1H, CHC(O)), 1.75-0.80 (m, 10H, cyclohexyl protons).

EXAMPLE 5

1-[N-(2-phenoxyphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine.3HCl

The title compound was prepared following the procedure described for the compound in example 3, except that 2-phenoxyaniline was used in place of 2-trifluoromethoxyaniline. The raw material was purified via flash chromatography (EtOAc). The residue was dissolved in ethanol, the solution was acidified by using 2 N HCl in ethanol and subsequently Et₂O was added giving 45% of the title compound after filtration. Melting point: 184-187° C.

¹H-NMR (DMSO-d₆, δ): 8.70-7.60 (m, 4H, 3⁺NH and NH), 7.32 (t, 2H, aromatics), 7.10-6.85 (m, 9H, aromatics), 6.80 (dd, 1H, aromatic), 6.63 (t, 1H, aromatic), 3.78 (s, 3H, OCH₃), 3.65-3.00 (m, 12H, piperazine protons and NHCH₂CH ₂).

EXAMPLE 6

1-[N-(2-phenoxyphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxy phenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 4, except that the compound in example 5 was used in place of the compound in example 3, then heated for 2.5 h at reflux. The crude was purified via flash chromatography (EtOAc- petrolium ether 7:3). Yield: 32%.

¹H-NMR (CDCl₃, δ): 7.40-7.20 (m, 4H, aromatics), 7.10 (t, 2H, aromatics), 7.05-6.80 (m, 7H, aromatics), 4.21-4.03 (m, 1H, C(O)NCH(H)CH₂), 3.83 (s, 3H, OCH₃), 3.55-3.40 (m, 1H, C(O)NC(H)HCH₂), 3.10-2.93 (m, 4H, piperazine protons), 2.75-2.50 (m, 6H, piperazine protons and C(O)NCH₂CH ₂), and 2.25-2.05 (m, 1H, CHC(O)), 1.80-0.80 (m, 10H, cyclohexyl protons).

EXAMPLE 7

1-[N-(2-iodophenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 3, except that 2-iodoaniline was used in place of 2-trifluoromethoxyaniline and heated at 90° C. for 7 h. The crude was purified via flash chromatography (EtOAc- petrolium ether 1:4). Yield: 37%.

¹H-NMR (CDCl₃, δ): 7.65 (dd, 1H, aniline H3), 7.20 (dd, 1H, aniline H5), 7.07-6.80 (m, 4H, methoxyphenyl ring CHs), 6.55 (dd, 1H, aniline H4), 6.45 (dd, 1H, aniline H6), 5.15-5.03 (br, 1H, NH), 3.87 (s, 3H, OCH₃), 3.30-3.05 (m, 6H, piperazine protons and NHCH ₂CH₂), 2.83-2.65 (m, 6H, piperazine protons and NHCH₂CH ₂).

EXAMPLE 8

1-[N-(2-iodophenyl)-N-cyclohexylcarbonyl-2-aminoethyll-4-(2-methoxyphenyl) piperazine

The title compound was prepared following the procedure described for the compound in example 4, except that the compound in example 7 was used in place of the compound in example 3, then heated for 7 h at reflux. Yield: 73%.

¹H-NMR (CDCl₃, δ): 8.95 (dd, 1H, iodophenyl ring H3), 7.45-7.35 (m, 2H, iodophenyl ring CHs), 7.15-6.80 (m, 5H, methoxyphenyl ring CHs and remaining iodophenyl ring CH), 4.53-4.37 (m, 1H, C(O)NCH(H)CH₂), 3.84 (s, 3H, OCH₃), 3.20-2.95 (m, 5H, C(O)NC(H)HCH₂ and piperazine protons), 2.77-2.50 (m, 7H, C(O)NCH₂CH ₂ piperazine protons and CHC(O)), 1.90-0.80 (m, 10H, cyclohexyl protons).

EXAMPLE 9

1-[N-(2-aminocarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 3, except that 2-aminobenzamide was used in place of 2-trifluoromethoxyaniline. The crude product was purified via flash chromatography (EtOAc) and subsequently crystallized by ethanol.

Yield: 36%. Melting point: 134-136° C.

¹H-NMR (CDCl₃, δ): 8.02-7.85 (br, 1H, NH), 7.41-7.26 (m, 2H, aniline H3,5), 7.05-6.78 (m, 4H, methoxyphenyl ring CHs), 6.73 (dd, 1H, aniline H6), 6.58 (t, 1H, aniline H4), 5.80-5.45 (br, 2H, CONH₂), 3.86 (s, 3H, OCH₃), 3.33 (t, 2H, NHCH ₂CH₂), 3.20-3.02 (m, 4H, piperazine protons), 2.83-2.62 (m, 6H, NHCH₂CH ₂, and piperazine protons).

EXAMPLE 10

1-[N-(2-cyanophenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

A mixture containing 0.2 g of the compound in example 9, 0.26 g of triphenylphosphine, 0.08 mL of triethylamine, 0.5 mL of CCl₄ and 10 mL of 1,2-dichloroethane was stirred for 3 h at reflux. The residue obtained after evaporation of the solvent was purified via flash chromatography (CH₂Cl₂-MeOH 98:2) giving 0.14 g (74%) of the title compound.

¹H-NMR (CDCl₃, δ): 7.40-7.30 (m, 2H, aniline H4,6), 7.05-6.80 (m, 4H, methoxyphenyl ring CHs), 6.70-6.57 (m, 2H, aniline H3,5), 5.45-5.30 (br, 1H, NH), 3.86 (s, 3H, OCH₃), 3.25 (q, 2H, NHCH ₂CH₂), 3.20-3.00 (m, 4H, piperazine protons), 2.85-2.60 (m, 6H, NHCH₂CH ₂ and piperazine protons).

EXAMPLE 11

1-[N-(2-acetylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

Preparation of 1-(N-phenyl-2-aminoethyl)-4-(2-methoxyphenyl)piperazine (Compound 11A)

The title compound was prepared following the procedure described for the compound in example 3, except that aniline was used in place of 2-trifluoromethoxyaniline and without solvent. The crude was purified via flash chromatography (petrolium ether-EtOAc 8:2). Yield: 77%

¹H-NMR (CDCl₃, δ): 7.30-7.10 (m, 2H, aniline H2,6), 7.10-6.80 (m, 4H, methoxyphenyl ring CHs), 6.80-6.58 (m, 3H, aniline H3,4,5), 4.35 (br, 1H, NH), 3.87 (s, 3H, OCH₃), 3.30-3.15 (m, 2, NHCH ₂CH₂), 3.15-2.98 (m, 4H, piperazine protons), 2.80-2.60 (m, 6H, piperazine protons and NHCH₂CH ₂).

1-[N-(2-acetylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

A solution of 1 M boron tribromide in CH₂Cl₂ (2.37 mL) was dropped into another solution containing 0.74 g of 1-(N-phenyl-2-aminoethyl)-4-(2-methoxyphenyl)piperazine in 10 ml, of CH₂Cl₂ stirred at −3° C. in nitrogen atmosphere. Subsequently, 0.25 mL of acetonitrile at room temperature was added and the mixture was stirred for 1h at room temperature and for 8 h until precipitation. After cooling at room temperature, the mixture was treated with a 10% aqueous solution of Na₂CO₃ and the organic phase that separated was dried on anhydrous Na₂SO₄ and evaporated to dryness. The crude was purified via flash chromatography (CH₂Cl₂-MeOH 98:2) and the residue crystallized from EtOH giving 0.33 g (39%) of the title compound. Melting point: 92-94° C.

¹H-NMR (CDCl₃, δ): 9.12-8.95 (br, 1H, NH), 7.75 (dd, 1H, aniline H3), 7.35 (dt, 1H, aniline H5), 7.05-6.80 (m, 4H, methoxyphenyl ring CHs), 6.73 (dd, 1H, aniline H4), 6.58 (dt, 1H, aniline H6), 3.86 (s, 3H, OCH₃), 3.35 (q, 2H, NHCH ₂CH₂), 3.20-3.02 (m, 4H, piperazine protons), 2.85-2.61 (m, 6H, NHCH₂CH ₂ and piperazine protons), 2.58 (s, 3H, COCH₃).

EXAMPLE 12

1-[N-(2-nitrophenyl)-2-aminoethyl]-4-(4-indolyl)piperazine

A mixture containing 0.49 g of N-(2-chloroethyl)-2-nitroaniline, prepared according to the procedure described by Ramage G. R. et al. in J. Chem. Soc. 4406-4409 (1952), 0.55 g of 1-(4-indolyl)piperazine (prepared according to WO 95/33743), 1 mL of triethylamine and 3 mL of DMF was heated at reflux while stirring under nitrogen for 2.5 h. After cooling at room temperature, the mixture was poured into H₂O, extracted with CH₂Cl₂, and the organic phase dried on anhydrous Na₂SO₄ and evaporated to dryness. The residue was purified via flash chromatography (EtOAc-petrolium ether 3:7) giving 0.35 g (40%) of the title compound.

¹H-NMR (CDCl₃, δ): 8.60-8.45 (br, 1H, aniline NH), 8.18 (dd, 1H, aniline H3), 8.20-8.10 (br, 1H, indole NH), 7.43 (td, 1H, aniline H5), 7.20-7.05 (m, 3H, indole H3,6,7), 6.85 (dd, 1H, aniline H4), 6.70-6.57 (m, 2H, aniline H6 and indole H5), 6.50 (t, 1H, indole H2), 3.45 (q, 2H, NHCH ₂CH₂), 3.35-3.25 (m, 4H, piperazine protons), 3.85-2.70 (m, 6H, NHCH ₂ and piperazine protons).

EXAMPLE 13

1-[N-(2-nitrophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-indolyl)piperazine

The title compound was prepared according to the procedure described for the compound in example 4, except that the compound in example 12 was used in place of the compound in example 3 and heated for 5 h at reflux. The crude was purified via flash chromatography (EtOAc-petrolium ether 7:3, then only EtOAc was used and at the end only CH₂Cl₂). Yield: 32%

¹H-NMR (CDCl₃, δ): 8.37-8.20 (br, 1H, NH), 8.05 (dd, 1H, nitrophenyl ring H3), 7.65-7.45 (m, 3H, nitrophenyl ring H4,5,6), 7.20-7.00 (m, 3H, indolyle H3,6,7), 6.55 (dd, 1H, indolyle H5), 6.50 (t, 1H, indolyle H2), 4.15-3.95 (m, 1H, C(O)NC(H)HCH₂), 3.70-3.55 (m, 1H, C(O)NCH(H)CH₂), 3.25-2.95 (m, 4H, piperazine protons), 2.75-2.45 (m, 7H, C(O)NCH₂CH _(2,)CHC(O), piperazine protons), 2.10-0.80 (m, 10H, cyclohexyl protons).

EXAMPLE 14

1-[N-(2-nitrophenyl)-2-aminoethyl)-4-(2,5-dichlorobenzyl)piperazine

Preparation of 1-(2,5-dichlorobenzyl)-4-ethoxycarbonylpiperazine (Compound 14A)

2,5-Dichlorobenzyl chloride (2.01 g) was added to a mixture of 1.94 g of 1-ethoxycarbonylpiperazine and 3.45 g of anhydrous potassium carbonate in 20 ml of N,N-dimethylformamide stirred at room temperature in nitrogen atmosphere. After 24 h of stirring at the same temperature, the reaction mixture was poured into water and extracted with ethyl acetate. The organic phase, which was dried on anhydrous Na₂SO₄, was evaporated to dryness under vacuum. The oily residue was purified via flash chromatography (petrolium ether-ethyl acetate 85:15) giving 2 g (63%) of the title compound.

¹H-NMR(CDCl₃, δ): 7.50 (d, 1H, aromatic H6), 7.27 (d, 1H, aromatic H3), 7.15 (dd, 1H, aromatic H4), 4.13 (q, 2H, CH₃CH ₂O), 3.58 (s, 2H, benzyl CH₂), 3.55-3.45 (m, 4H, piperazine protons), 2.50-2.42 (m, 4H, piperazine protons), 1.26 (t, 3H, CH ₃CH₂O).

Preparation of 1-(2,5-dichlorobenzyl)piperazine (Compound 14B)

A solution containing 13 g of 1-(2,5-dichlorobenzyl)-4-ethoxycarbonylpiperazine in 35 mL of 37% HCl was stirred for 40 h at reflux. Subsequently, 30 mL of water and 30 mL of EtOAc were added at room temperature, adjusting the pH to 11 via addition of 35% NaOH. The organic phase, which was dried on anhydrous sodium sulphate, was evaporated to dryness under vacuum. The crude was purified via flash chromatography (CHCl₃-MeOH 7:3) giving 4.46 g (50%) of the title compound.

¹H-NMR (CDCl₃, δ): 7.50 (d, 1H, aromatic H6), 7.26 (d, 1H, aromatic H3), 7.14 (dd, 1H, aromatic H4), 3.55 (s, 2H, benzyl CH₂), 3.00-2.85 (m, 4H, piperazine protons), 2.55-2.48 (m, 4H, piperazine protons), 1.76 (s, 1H, NH).

Preparation of 1-[N-(2-nitrophenyl)-2-aminoethyl]-4-(2,5-dichlorobenzyl)piperazine

This compound was prepared and purified following the method described for the compound in example 12, except that 1-(2,5-dichlorobenzyl)piperazine was used in place of 1-(4-indolyl)piperazine and 4-dimethylaminopyridine was used in place of triethylamine, carrying out the reaction at 120° C. for 8 h. Yield: 35%.

¹H-NMR (CDCl₃, δ): 8.45 (br, 1H, NH), 8.10 (d, 1H, aniline H3), 7.45 (d, 1H, dichlorophenyl ring H6), 7.38 (dd, 1H, aniline H5), 7.25 (d, 1H, dichlorophenyl ring H3), 7.10 (dd, 1H, dichlorophenyl ring H4), 6.77 (d, 1H, aniline H6), 6.55 (dd, 1H, aniline H4), 3.59 (s, 2H, benzyl CH₂), 3.35 (dt, 2H, NHCH ₂CH₂), 2.73 (t, 2H, NHCH₂CH ₂), 2.70-2.38 (m, 8H, piperazine protons).

EXAMPLE 15

1-[N-(2-nitrophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2,5-dichlorobenzyl)piperazine

The title compound was prepared following the procedure described for the compound in example 2, except that the compound in example 14 was used in place of the compound in example 1 and heated for 12 h at reflux. The crude was purified via flash chromatography (EtOAc-petrolium ether 4:6). Yield: 22%.

¹H-NMR (CDCl₃, δ): 8.03 (dd, 1H, nitrophenyl ring H3), 7.75-7.40 (m, 4H, dichlorophenyl ring H6 and nitrophenyl ring H4,5,6), 7.25 (d, 1H, dichlorophenyl ring H3), 7.10 (dd, 1H, dichlorophenyl ring H4), 4.05-3.90 (m, 1H, C(O)NCH(H)CH₂), 3.65-3.50 (m, 1H, C(O)NC(H)HCH₂, 3.52 (s, 2H, benzyl CH₂), 2.70-2.20 (m, 10H, C(O)NCH₂CH ₂, piperazine protons), 2.00-0.70 (m, 11H, cyclohexyl protons).

EXAMPLE 16

1-[N-(2-cyclohexylcarbonylaminocarbonylphenyl)-N-cyclohexylcarbonyl-2-amino ethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 4, except that the compound in example 9 was used in place of the compound in example 3 and the reaction was carried out for 6 h at reflux in the presence of 2 molar equivalents of cyclohexylcarbonyl chloride. The crude was purified via flash chromatography (CH₂Cl₂-MeOH 95:5). Yield: 55%.

¹H-NMR (DMSO-δ₆, δ): 12.10-11.80 (br, 1H, NH), 8.08 (dd, 1H, phenylcarbonyl H3), 7.88-7.68 (m, 2H, phenylcarbonyl H5,6), 7.47 (dt, 1H, phenylcarbonyl H4), 7.00-6.80 (m, 4H, methoxyphenyl ring CHs), 4.50-4.33 (m, 2H, C(O)NCH ₂CH₂), 3.75 (s, 3H, OCH₃), 3.15-2.85 (m, 5H, CHC(O) and piperazine protons), 2.80-2.68 (m, 2H, C(O)NCH₂CH ₂), 2.68-2.54 (m, 4H, piperazine protons), 2.28-2.08 (m, 1H, CHC(O)), 1.97-1.05 (m, 20H, cyclohexyl protons).

EXAMPLE 17

1-[N-(2-methoxycarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

A mixture of 0.93 g of methyl anthranilate, 2 g of 1-(2-chloroethyl)-4-(2-methoxyphenyl)piperazine, 0.88 g of sodium acetate and 5 mL of H₂O was stirred for 24 h at reflux. After cooling at room temperature, the mixture was extracted with EtOAc, the organic phase dried on Na₂SO₄, evaporated to dryness and the residue purified via flash chromatography (CH₂Cl₂-MeOH 98:2) giving 0.41 g (18%) of the title compound.

¹H-NMR (CDCl₃, δ): 7.90 (dd, 1H, aniline H3), 7.90-7.70 (br, 1H, NH), 7.35 (td, 1H, aniline H5), 7.06-6.80 (m, 4H, methoxyphenyl ring CHs), 6.70 (dd, 1H, aniline H6), 6.58 (td, 1H, aniline H4), 3.87 and 3.85 (2s, 6H, COOCH₃ and OCH₃), 3.43-3.30 (m, 2H, NHCH ₂CH₂), 3.22-3.05 (m, 4H, piperazine protons), 2.83-2.67 (m, 6H, NHCH₂CH ₂ and piperazine protons).

EXAMPLE 18

1-[N-(2-methoxycarbonylphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 4, except that the compound in example 17 was used in place of the compound in example 3 and the reaction was carried out for 9 h at reflux. The crude was purified by flash chromatography (CH₂Cl₂-MeOH 95:5). Yield: 38%

¹H-NMR (CDCl₃, δ): 8.03 (dd, 1H, methoxycarbonylphenyl ring H3), 7.57 (dt, 1H , methoxycarbonylphenyl ring H 4), 7.45 (dt, 1H, methoxycarbonylphenyl ring H5), 7.37 (dd, 1H, methoxycarbonylphenyl ring H6), 7.03-6.80 (m, 4H, methoxyphenyl ring CHs), 4.38-4.15 (m, 1H, C(O)NCH(H)CH₂), 3.86 and 3.83 (2s, 6H, COOCH₃ and OCH₃), 3.33-3.15 (m, 1H C(O)NC(H)HCH₂), 3.10-2.93 (m, 4H, piperazine protons), 2.75-2.50 (m, 4H, piperazine protons), 2.56 (t, 2H, C(O)NCH₂CH ₂), 2.00-1.83 (m, 1H, CHC(O)), 1.80-0.80 (m, 10H, cyclohexyl protons).

EXAMPLE 19

1-[N-(2-dimethylaminocarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl) piperazine.

The title compound was prepared following the procedure described for the compound in example 3, except that N,N-dimethyl-2-aminobenzamide was used in place of 2-trifluoromethoxyaniline. The crude was purified via flash chromatography (EtOAc-MeOH 97:3). Yield: 19%

¹H-NMR (CDCl₃, δ): 7.25 (dt, 1H, aniline H5), 7.09 (dd, 1H, aniline H3), 7.06-6.80 (m, 4H, methoxyphenyl ring CHs), 6.68 (dd, 1H, aniline H6), 6.66 (dt, 1H, aniline H4), 5 50-5.10 (br, 1H, NH), 3.86 (s, 3H, OCH₃), 3.23 (t, 2H, NHCH ₂CH₂), 3.18-3.08 (m, 4H, piperazine protons), 3.05 (s, 6H, N(CH₃)₂), 2.78-2.62 (m, 6H, NHCH₂CH ₂ and piperazine protons).

EXAMPLE 20

1-[N-(2-methoxyphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared and purified following the procedure described for the compound in example 3, except that 2-methoxyaniline was used in place of 2-trifluoromethoxyaniline, and heated at 100° C. for 4 h. Yield: 50%

¹H-NMR (CDCl₃, δ): 7.05-6.85 (m, 5H, methoxyphenyl ring CHs and aniline CH), 6.85-6.60 (m, 3H, aniline CHs), 3.87 and 3.85 (2s, 6H, 2 OCH₃), 3.25 (t, 2H, NHCH ₂CH₂), 3.18-3.05 (m, 4H, piperazine protons), 2.80-2.65 (m, 6H, NHCH₂CH ₂ and piperazine protons).

EXAMPLE 21

1-[N-(2-dimethylaminocarbonylphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine.

The title compound was prepared following the procedure described for the compound in example 4, except that the compound in example 19 was used in place of the compound in example 3, 1,2-dichloroethane was used in place of dichloromethane, and the mixture was refluxed for 5 h. The crude was purified by flash chromatography (CH₂Cl₂-MeOH 93:7). Yield: 36%.

¹H-NMR (CDCl₃, δ): 7.50-7.30 (m, 4H, benzamide ring CHs), 7.06-6.80 (m, 4H, methoxyphenyl ring CHs), 4.85 (s, 3H, OCH₃), 4.60-4.40 (m, 1H, CONCH(H)CH₂N), 3.67-3.40 (m, 1H, CONCH(H)CH₂N), 3.35-2.95 (m, 4H, piperazine protons), 3.10 and 2.90 (2s, 6H, N(CH₃)₂), 2.85-2.45 (m, 6H, piperazine protons and CONCH₂CH₂N), 2.10-1.90 (m, 1H, CHC(O)), 1.90-0.80 (m, 10H, cyclohexyl protons).

EXAMPLE 22

1-[N-(2-trifluoromethylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 3, except that 2-trifluoromethylaniline was used in place of 2-trifluoromethoxyaniline. The crude was purified via flash chromatography (EtOAc-petroleum ether 2:8). Yield: 14%.

¹H-NMR (CDCl₃, δ): 7.50-7.30 (m, 4H, aniline CHs), 7.10-6.80 (m, 4H, methoxyphenyl ring CHs), 5.50-5.38 (br, 1H, NH), 3.86 (s, 3H, OCH₃), 3.30-3.18 (m, 2H, NHCH ₂CH₂), 3.18-3.05 (m, 4H, piperazine protons), 2.75 (t, 2H, NHCH₂CH ₂), 2.80-2.63 (m, 4H, piperazine protons).

EXAMPLE 23

1-[N-(2-methoxyphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxy phenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 2, except that the compound in example 20 was used in place of the compound in example 1 and the mixture was refluxed for 6 h. The crude was purified by flash chromatography (CH₂Cl₂-MeOH 9.5:0.5). Yield: 59%.

¹H-NMR (CDCl₃, δ): 7.38 (dd, 1H, methoxyphenylaniline H6), 7.26 (dd, 1H, methoxyphenylaniline H4), 7.10-6.85 (m, 6H, methoxyphenylaniline H3, H5 and methoxyphenyl protons), 4.35-4.12 (m, 1H, CONCH(H)CH₂), 3.89 (s, 3H, OCH₃), 3.86 (s, 3H, OCH₃), 3.55-3.33 (m, 1H, CONCH(H)CH₂), 3.20-2.98 (m, 4H, piperazine protons), 2.80-2.50 (m, 6H, piperazine protons and CONCH₂CH ₂), 2.05 (tt, 1H, CHC(O)), 1.30-0.85(m, 10H, cyclohexyl protons).

EXAMPLE 24

1-[N-(2-ethylaminocarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine.

The title compound was prepared following the procedure described for the compound in example 3, except that 2-amino-N-ethylbenzamide was used in place of 2-trifluoromethoxyaniline and the mixture was refluxed for 5 h. The crude was purified by flash chromatography (CH₂Cl₂-MeOH 9.7:0.3). Yield: 12%.

¹H-NMR (CDCl₃, δ): 7.50 (t, 1H, CONHEt),7.38-7.23 (m, 2H, aniline H4, H6), 7.07-6.83 (m, 4H, methoxyphenyl ring CHs), 6.70 (dd, 1H, aniline H3), 6.60 (dd, 1H, aniline H 5), 6.13-5.90 (br, 1H, NHCH₂CH₂), 3.86 (s, 3H, OCH₃), 3.53-3.40 (m, 2H, CONHCH ₂CH₃), 3.33 (q, 2H, NHCH ₂CH₂), 3.18-3.02 (m, 4H, piperazine protons), 2.83-2.63 (m, 6H, piperazine protons and NHCH₂CH ₂), 1.23 (t, 3H, CONHCH₂CH ₃).

EXAMPLE 25

1-[N-(2-ethylaminocarbonylphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 2, except that the compound in example 24 was used in place of the compound in example 1, (toluene instead of 1,2-dichloeroethane), and the mixture was refluxed for 12 h. The crude was purified by flash chromatography (CH₂Cl₂-MeOH 9.5:0.5). Yield: 43%.

¹H-NMR (CDCl₃, δ): 9.30-9.12 (br, 1H, CONHEt), 7.80 (dd, 1H, aniline H6), 7.45 (dd, 1H, aniline H4), 7.35 (dd, 1H, aniline H5), 7.20 (dd, 1H, aniline H3), 7.05-6.75 (m, 4H, methoxyphenyl ring CHs), 4.47 (dt, 1H, CONCH(H)CH₂N), 3.82 (s, 3H, OCH₃), 3.73-3.50 (m, 1H, CONHCH(H)CH₃), 3.32-3.10 (m, 1H, CONHCH(H)CH₃), 3.03-2.25 (m, 5H, CONCH(H)CH₂N and piperazine protons), 2.65-2.16 (m, 7H, CONCH₂CH ₂, piperazine protons and CHC(O)), 1.70-0.80 (m, 10H, cyclohexyl protons), 1.18 (t, 3H, CONHCH₂CH ₃).

EXAMPLE 26

1-[N-(2-trifluoromethylphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine.

Preparation of N-(2-trifluoromethylphenyl)cyclohexanecarboxamide (Compound 26A)

A solution of 2-trifluoromethylaniline (3 mL), triethylamine (3.5 mL) and CH₂Cl₂ (30 mL) was stirred at room temperature under N₂ and added dropwise with cyclohexanecarbonyl chloride (3.34 mL). After 2.5 h stirring at room temperature, the mixture was poured into H₂O and alkalinized with 1 N NaOH. The organic phase was dried on anhydrous Na₂SO₄ and the crude was crystallized from EtOH to give 3.82 g (59%) of the title compound. M. p. 153-154° C.

¹H-NMR (CDCl₃, δ): 8.20 (dd, 1H, trifluoromethylphenyl ring CH), 7.60-7.40 (m, 3H, trifluoromethylphenyl ring CHs and NH), 7.12 (ddd, 1H, trifluoromethylphenyl ring CH), 2.30 (tt, 1H, CHC(O)), 2.10-1.20 (m, 10H, cyclohexyl protons).

Preparation of 1-[N-(2-trifluoromethylphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

A mixture of N-(2-trifluoromethylphenyl)cyclohexanecarboxamide (0.2 g) (Compd 26A), 1-(2-chloroethyl)-4-(2-methoxyphenyl)piperazine (0.37 g),50% (w/w) NaOH (0.5 mL), TEBAC (0.16 g) and toluene (2 mL) was stirred at 80° C. for 3.5 h. An additional amount of compd 26A (0.2 g) was then added and after 6 h stirring at 80° C. the mixture was poured into H₂O and extracted with CH₂Cl₂. The organic phase was dried on anhydrous Na₂SO₄, evaporated to dryness and the residue purified by flash chromatography (EtOAc-petroleum ether 3:7) giving 0.12 g (17%) of the title compound.

¹H-NMR (CDCl₃, δ): 7.77 (dd, 1H, trifluoromethylphenyl ring CH), 7.70-7.45 (m, 3H, trifluoromethylphenyl ring CHs), 7.10-6.80 (m, 4H, methoxyphenyl ring CHs), 4.70-4.50 (m, 1H, CONCH(H)CH₂N), 3.85 (s, 3H, OCH₃), 3.20-2.90 (m, 5H, CONCH(H)CH₂N and piperazine protons), 2.85-2.45 (m, 7H, CHC(O), CONCH₂CH ₂N and piperazine protons), 1.90-0.75 (m, 10H, cyclohexyl protons).

EXAMPLE 27

1-[N-(2-aminophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl) piperazine

A mixture of 1.05 g of the compound in example 2, 2 mL of hydrazine H₂O and 1 g of Raney nickel in 70 mL of MeOH was stirred at 50° C. for 1.5 h. The insoluble was separated by filtration and the solution was evaporated to dryness. The residue was crystallized from EtOH to give 0.69 g (71%) of the title compound. Melting point: 138.5-140° C.

¹H-NMR (CDCl₃, δ): 7.15 (dd, 1H, aminophenyl ring CH), 7.10-6.80 (m, 5H, aminophenyl ring CH and methoxyphenyl ring CHs), 6.80-6.65 (m, 2H, aminophenyl ring CHs), 4.96 (s, 2H, NH₂), 4.96-4.65 (m, 1H, CONCH(H)CH₂N), 3.86 (s,3H, OCH₃), 3.20-2.80 (m,7H, CONCH(H)CH ₂N and piperazine protons), 2.45-2.65 (m, 4H, piperazine protons), 2.10 (tt, 1H, CH(O)), 1.90-0.80 (m, 10H, cyclohexyl protons).

EXAMPLE 28

1-[N-(2-acetylaminophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

To a stirred solution of 0.22 g of the compound described in example 27 and 0.08 mL of triethylamine in 5 mL of CH₂Cl₂ was added a solution of 0.04 mL of acetyl chloride in 0.5 mL CH₂Cl₂ at room temperature. After 2 h stirring at the same temperature, the solvent was evaporated to dryness and the residue purified by flash chromatography (CH₂Cl₂—CH₃CN 98:2) to give 0.12 g (50%) of the title compound.

¹H-NMR (CDCl₃, δ): 9.90 (s, 1H, NH), 7.85 (dd, 1H, acetylaminophenyl ring CH), 7.40 (td,1H, acetylaminophenyl ring CH), 7.23-7.10 (m, 2H, acetylaminophenyl ring CHs), 7.05-6.80 (m, 4H, methoxyphenyl ring CHs), 5.00-4.80 (m, 1H, CONCH(H)CH₂N), 3.83 (s, 3H, OCH₃), 3.20-2.25 (m, 11H, CONCH(H)CH ₂N and piperazine protons), 2.15 (s, 3H, COCH₃), 2.05-1.85 (m, 1H, CHC(O)), 1.75-0.80 (m, 10H, cyclohexyl protons).

EXAMPLE 29

1-[N-(2-nitrophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine N¹-oxide

A suspension of 0.89 g of 83% magnesium monoperoxyphthalate .0.6 H₂O in 10 mL of H₂O was added dropwise into a solution of 1.4 g of the compound described in example 2 in 10 mL of CHCl₃ and 45 mL of MeOH at 5° C.

After overnight resting at room temperature, the solvents were evaporated to dryness and the residue was treated with 50 mL of H₂O, alkalinized with 20% Na₂CO₃ and extracted with CHCl₃. The organic phase was dried on anhydrous Na₂SO₄ and evaporated to dryness. The residue was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ gradient 100:7 to 100:20) to give 0.5 g of a crude, that was crystallized from Me₂CO yielding 0.35 g (24%) of the title compound. Melting point: 128-132° C.

¹H-NMR (CDCl₃, δ): 8.05 (dd, 1H, nitrophenyl ring H3), 7.70 (ddd, 1H, nitrophenyl ring H5), 7.50 (ddd, 1H, nitrophenyl ring H4), 7.41 (dd, 1H, nitrophenyl ring H6), 7.07-6.76 (m, 4H, methoxyphenyl ring CHs), 4.40-4.12 (m, 2H, CONCH ₂CH₂N), 3.85 (s, 3H, OCH₃), 3.70-3.5 (m, 6H, CONCH₂CH ₂N and piperazine protons), 3.35-3.07 (m, 4H, piperazine protons), 2.05-1.80 (m, 1H CHC(O)), 1.75-0.75 (m, 10H, cyclohexyl protons).

EXAMPLE 30

1-[N-(2-nitrophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine N⁴-oxide

The title compound was isolated during purification of the compound described in example 29. Yield 0.23 g (16%) as a vitreous solid.

¹H-NMR(CDCl₃, δ): 8.75 (dd, 1H, methoxyphenyl ring H6), 8.05 (dd, 1H, nitrophenyl ring H3), 7.71 (ddd, 1H, nitrophenyl ring H5), 7.57 (ddd, 1H, nitrophenyl ring H4), 7.47 (dd, 1H, nitrophenyl ring H6), 7.37 (ddd, 1H, methoxyphenyl ring H4 (H5)), 7.10 (ddd, 1H, methoxyphenyl ring H5 (H4)), 6.98 (dd, 1H, methoxyphenyl ring H3), 4.72-4.41 (m, 2H, piperazine protons), 4.03 (s, 3H, OCH₃), 3.83 (t, 2H, CONCHCH₂N), 3.35-3.09 (m, 2H, piperazine protons), 2.98-2.77 (m, 2H, CONCH,₂CH ₂N), 2.77-2.30 (m, 4H, piperazine protons), 2.05-0.83 (m, 11H, cyclohexyl protons).

EXAMPLE 31

1-[N-(2-nitrophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine N¹,N⁴-dioxide

The title compound was synthesized as described for example 29 but using equimolar amounts of magnesium monoperoxyphthalate and compound described in example 2. Yield 43% after crystallization from CH₃CN. Melting point: 153-157° C.

¹H-NMR (CDCl₃, δ): 8.70 (dd, 1H, methoxyphenyl ring H6), 8.05 (dd, 1H, nitrophenyl ring H3), 7.70 (ddd, 1H, nitrophenyl ring H5), 7.58 (ddd, 1H, nitrophenyl ring H4), 7.49-7.32 (m, 2H, nitrophenyl ring H6 and methoxyphenyl ring H4), 7.13 (ddd, 1H, methoxyphenyl ring H5), 7.00 (dd, 1H, methoxyphenyl ring H3), 5.92-5.67 (m, 2H, piperazine protons), 4.70-4.45 (m, 2H, piperazine protons), 4.45-4.05 (m, 2H, CONCH ₂CH₂N),4.00 (s,2H, CONCH₂CH ₂N), 3.30-3.08 (m, 2H, piperazine protons), 3.05-2.85)m, 2H, piperazine protons), 2.05-1.78 (m, 1H, CHC(O)), 1.78-0.70 (m, 10H, cyclohexyl protons).

EXAMPLE 32

1-[N-(2-nitrophenyl)-N-(3-furylcarbonyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

A suspension of 0.77 g of the monohydrochloride of compound described in example 1 in 50 mL of toluene was stirred at reflux removing about 20 mL of distillate. After cooling to 60-70° C., 0.9 mL of 97% diisopropylethylamine (DIPEA) was added and the mixture stirred for 15′. 0.66 g of 3-furylcarbonyl chloride was then added to the mixture that was stirred at reflux for 5 h, cooled to room temperature, washed in the sequence with H₂O, 1 N NaOH and H₂O, dried on anhydrous Na₂SO₄ and evaporated to dryness. The residue was purified by flash chromatography (EtOAc-petroleum ether gradient 1:1 to 7:3) affording 0.67 g (75%) of the title compound.

¹H-NMR (CDCl₃, δ): 8.05 (dd, 1H, nitrophenyl ring H3), 7.73-7.58 (m, 2H, nitrophenyl ring H5 and H6), 7.58-7.45 (m, 1H, nitrophenyl ring H4), 7.15 (br, 1H, furan ring H2), 7.02-6.77 (m, 5H, furan ring H5 and methoxyphenyl ring CHs), 6.13 (br, 1H, furan ring H4), 4.30-4.08 (m, 1H, CONCH(H)CH₂N), 3.90-3.70 (m, 1H, CONCH(H)CH₂N), 3.83 (s, 3H,OCH₃), 3.05-2.80 (m, 4H, piperazine protons), 2.80-2.62 (m, 2H, CONCH₂CH ₂N), 2.62-2.45 (m, 4H, piperazine protons).

EXAMPLE 33

1-[N-(2-nitrophenyl)-N-(2-furylcarbonyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 32, except that 2-furylcarbonyl chloride was used in place of 3-furancarbonyl chloride. Yield 77%.

¹H-NMR (CDCl₃, δ): 8.05 (dd, 1H, nitrophenyl ring H3), 7.72-7.45 (m, 3H, other nitrophenyl ring CHs), 7.20 (br, 1H, furan ring H3), 7.05-6.75 (m, 4H, methoxyphenyl ring CHs), 6.49 (br, 1H, furan ring H4), 6.25 (br, 1H, furan ring H5), 4.30-4.10 (m, 1H, CONCH(H)CH₂N), 3.98-3.75 (m, 1H, CONCH(H)CH₂N), 3.83 (s, 3H,OCH₃), 3.15-2.85), (m, 4H, piperazine protons 2.85-2.65 (m, 2H, CONCH₂CH ₂N), 2.65-2.48 (m, 4H, piperazine protons).

EXAMPLE 34

1-[N-(2-nitrophenyl)-N-(2-thiophenecarbonyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 32, except that 2-thiophenecarbonyl chloride was used in place of 3-furylcarbonyl chloride and reflux lasted 8 h. Yield 59%.

¹H-NMR (CDCl₃, δ): 8.03 (dd, 1H, nitrophenyl ring H3), 7.71-7.60 (m, 2H, nitrophenyl ring H5 and H6), 7.60-7.45 (m, 1H, nitrophenyl ring H4), 7.27 (dd, 1H thiophene ring H3 (H5)), 7.05-6.70 (m, 6H, thiophene H4 and H5 (H3) and methoxyphenyl ring CHs), 4.22-4.10 (m, 1H, CONCH(H)CH₂N), 3.92-3.71 (m, 1H CONCH(H)CH₂N), 3.80 (s, 3H,OCH₃), 3.10-2.80 (m, 4H, piperazine protons), 2.80-2.65 (m, 2H, CONCH₂CH ₂N), 2.65-2.45 (m, 4H, piperazine protons).

EXAMPLE 35

1-[N-(2-nitrophenyl)-N-(3-thiophenecarbonyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 32, except that 3-thiophenecarbonyl chloride was used in place of 3-furylcarbonyl chloride and reflux lasted 7 h. Yield 88%.

¹H-NMR (CDCl₃, δ): 7.93 (dd, 1H, nitrophenyl ring H3), 7.70-7.55 (m, 2H, nitrophenyl ring H5 and H6), 7.48-7.35 (m, 1H, nitrophenyl ring H4), 7.25-7.12 (m, 1H, thiophene ring H2), 7.12-7.02 (m, 1H, thiophene ring H5) 7.02-6.91 (m, 1H, thiophene ring H4), 6.91-6.78 (m, 4H, methoxyphenyl ring CHs), 4.32-4.10 (m, 1H, CONCH(H)CH₂N), 3.90-3.70 (m, 1H, CONCH(H)CH₂N), 3.81 (s, 3H, OCH₃), 3.05-2.78 (m, 4H, piperazine protons), 2.78-2.65 (m, 2H, CONCH₂CH ₂N), 2.65-2.45 (m, 4H, piperazine protons).

EXAMPLE 36

1-[N-(2-nitrophenyl)-N-(4-pyridylcarbonyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 32, except that 4-pyridylcarbonyl chloride was used in place of 3-furylcarbonyl chloride and reflux lasted 14 h. The crude was purified by flash chromatography (CHCl₃-2.5 N methanolic NH₃ gradient 100:1.5 to 100:3). Yield 39%.

¹H-NMR (CDCl₃, δ): 8.42 (dd, 2H, pyridine ring H2 and H6), 7.90 (dd, 1H, nitrophenyl ring H3), 7.62-7.45 (m, 2H, nitrophenyl ring H5 and H6), 7.45-7.30 (m, 1H, nitrophenyl ring H4), 7.15 (dd 2H, pyridine ring H3 and H5) 7.08-6.75 (m, 4H, methoxyphenyl ring CHs), 4.50-4.20 (m, 1H, CONCH(H)CH₂N), 3.90-3.65 (m, 1H, CONCH(H)CH₂N), 3.80 (s, 3H, OCH₃), 3.15-2.28 (m, 10H, CONCH₂CH ₂N and piperazine protons).

EXAMPLE 37

1-[N-(2-nitrophenyl)-N-(3-pyridylcarbonyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 32, except that 3-pyridylcarbonyl chloride was used in place of 3-furylcarbonyl chloride and reflux lasted 12 h. The crude was purified by flash chromatography (CHCl₃-2.5 N methanolic NH₃ 100:3). Yield 46%.

¹H-NMR (CDCl₃, δ): 8.50-8.35 (m, 2H, pyridine ring H2 and H6), 7.90 (dd, 1H, nitrophenyl ring. H3), 7.72 (dd, 1H, pyridine ring H4), 7.60-7.50 (m, 2H, nitrophenyl ring H5 and H6), 7.43--7.28 (m, 1H, nitrophenyl ring H4) 7.30-7.15 (m, 1H, pyridine ring H5), 7.03-6.76 (m, 4H, methoxyphenyl ring CHs), 4.35-4.15 (m, 1H, CONCH(H)CH₂N), 4.00-3.75 (m, 1H, CONCH(H)CH₂N), 3.80 (s, 3H,OCH₃), 3.10-2.40 (m, 10H, CONCH₂CH ₂N and piperazine protons).

EXAMPLE 38

1-[N-(2-nitrophenyl)-N-(2-pyrazinylcarbonyl )-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 32, except that 2-pyrazinylcarbonyl chloride was used in place of 3-furylcarbonyl chloride and reflux lasted 1h. The crude was purified by flash chromatography (CHCl₃-2.5 N methanolic NH₃ gradient 100:1 to 100:3). Yield 89%.

¹H-NMR(CDCl₃, δ): 9.08 (d, 1H pyrazine ring H3), 8.40(d, 1H, pyrazine ring H6), 8.07 (d, 1H, pyrazine ring H5), 7.97 (dd, 1H, nitrophenyl ring H3), 7.62-7.50 (m, 2H, nitrophenyl ring H5 and H6) 7.48-7.31 (m, 1H, nitrophenyl ring H4), 7.05-6.80 (m, 4H, methoxyphenyl ring CHs), 4.31-4.15 (m, 1H, CONCH(H)CH₂N), 4.08-3.92 (m, 1H, CONCH(H)CH₂N), 3.82 (s, 3H,OCH₃), 3.05-2.40 (m, 10H, CONCH₂CH ₂N and piperazine protons).

EXAMPLE 39

1-[N-(2-nitrophenyl)-N-(1-methylcyclohexylcarbonyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

Preparation of 1-methyl-N-(2-nitrophenyl)cyclohexanecarboxamide (Compound 39A)

This compound was prepared following the procedure described for compound 26A in example 26, except that 1-methylcyclohexanecarbonyl chloride (J. Org. Chem. 47, 3242 (1982)) was used in place of cyclohexanecarbonyl chloride and the reaction mixture was refluxed for 50 h. The crude was purified by flash chromatography (petroleum ether-EtOAc 100:2). Yield 90%.

¹H-NMR (CDCl₃, δ): 10.75 (s, 1H, NH), 8.85 (dd, 1H, nitrophenyl ring H6), 8.22 (dd, 1H, nitrophenyl ring H3), 7.62 (ddd, 1H, nitrophenyl ring H5), 7.15 (ddd, 1H, nitrophenyl ring H4) 2.20-1.95 (m, 2H, cyclohexyl protons), 1.75-1.35 (m, 8H, cyclohexyl protons), 1.25 (s, 3H, CH₃).

Preparation of 1-[N-(2-nitrophenyl)-N-(1-methylcyclohexylcarbonyl)-2-aminoethyl]-4- (2-methoxyphenyl)piperazine

A mixture of 0.3 g of 1-methyl-N-(2-nitrophenyl)cyclohexanecarboxamide (compound 39A), 50 mL of toluene and 0.26 g of tert-BuOK was stirred at reflux removing about 11 ml, of distillate, then a solution of 0.32 g of 1-(2-chloroethyl)-4-(2-methoxyphenyl)piperazine in 10 mL of toluene was added to the mixture. After 16 h stirring at reflux, the mixture was cooled and washed with H₂O, the organic layer was dried on anhydrous Na₂SO₄ and evaporated to dryness. The crude was purified by flash chromatography (petroleum ether - EtOAc 7:3) to give 0.51 g (43%) of the title compound.

¹-NMR (CDCl₃, δ): 7.98 (dd, 1H,nitrophenyl ring H3), 7.40 (ddd, 1H, nitrophenyl ring H5), 7.08-6.80 (m, 6H, nitrophenyl ring H4 and H6 and methoxyphenyl ring CHs), 4.31-4.10 (m, 2H, CONCH ₂CH₂), 3.85 (s, 3H,OCH₃), 3.20-2.98 (m, 4H, piperazine protons), 2.88-2.62 (m, 6H, CONCH₂CH ₂ and piperazine protons), 1.90-1.70 (m, 2H, cyclohexyl protons), 1.53-1.22 (m, 8H, cyclohexyl protons), 1.18 (s, 3H, CH₃).

EXAMPLE 40

1-[N-(2-nitrophenyl)-N-(1-phenylcyclohexylcarbonyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

Preparation of 1-phenyl-N-(2-nitrophenyl)cyclohexanecarboxamide(Compound 40A)

This compound was prepared following the procedure described for compound 39A in example 39, except that 1-phenylcyclohexanecarbonyl chloride (J. Am. Chem. Soc. 68, 2345-7 (1946)) was used in place of 1-methylcyclohexanecarbonyl chloride, toluene in place of CH₂Cl₂, DIPEA in place of triethylamine and reaction mixture was refluxed for 15 h. The crude was purified by flash chromatography (petroleum ether-EtOAc 98:2). Yield 91%.

¹H-NMR (CDCl₃, δ): 10.32 (s, 1H, NH), 8.76 (dd, 1H, nitrophenyl ring H6), 8.12 (dd, 1H, nitrophenyl ring H3), 7.64-7.32 (m, 5H, phenyl ring CHs), 7.28 (ddd, 1H nitrophenyl ring H5), 7.08 (ddd, 1H, nitrophenyl ring H4), 2.54-2.34 (m, 2H, cyclohexyl protons), 2.22-2.02 (m, 2H, cyclohexyl protons), 1.76-1.28 (m, 6H, cyclohexyl protons).

Preparation of 1-[N-(2-nitrophenyl)-N-(1-phenylcyclohexylcarbonyl)-2-aminoethyl]-4-(2-methoxyphenylpiperazine

The title compound was prepared following the procedure described for compound in example 39, except that compound 40A was used in place of 1-methyl-N-(2-nitrophenyl)cyclohexanecarboxamide and reflux lasted 22 h. The crude was purified by flash chromatography (petroleum ether-EtOAc gradient 8:2 to 7:3). Yield 37%.

¹H-NMR (CDCl₃, δ): 7.90 (dd, 1H, nitrophenyl ring H3), 7.45-7.10 (m, 7H, phenyl ring CHs and nitrophenyl ring H5 and H6), 7.04-6.78 (m, 5H, nitrophenyl ring H4 and methoxyphenyl ring CHs), 4.30-4.12 (m, 2H, CONCH ₂CH₂), 3.82 (s, 3H, OCH₃), 3.18-2.93 (m, 4H, piperazine protons), 2.80-2.50 (m, 6H, CONCH₂CH ₂ and piperazine protons), 2.30-2.10 (m, 2H, cyclohexyl protons), 1.92-1.75 (m, 2H, cyclohexyl protons), 1.74-1.35 (m, 6H, cyclohexyl protons).

EXAMPLE 41

1-[N-[2-(2,2,2-trifluoroethoxy)phenyl]-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for compound in example 3, except that 2-(2,2,2-trifluoroethoxy)aniline (EP 748800) was used in place of 2-trifluoromethoxyaniline and the reaction mixture was refluxed for 7 h. The crude was purified by flash chromatography (petroleum ether-EtOAc gradient 9:1 to 8:2). Yield 38%.

¹H-NMR(CDCl₃, δ): 7.08-6.80 (m, 5H, methoxyphenyl ring CHs and trifluoroethoxyphenyl ring CH), 6.80-6.57 (m, 3H, trifluoroethoxyphenyl ring CHs), 5.11-4.70 (m, 1H, NH), 4.35 (q, 2H, OCH₂CF₃), 3.85 (s, 3H,OCH₃), 3.38-3.19 (m, 2H, NHCH ₂CH₂), 3.19-2.98 (m, 4H, piperazine protons), 2.88-2.60 (m, 6H, NHCH₂CH ₂ and piperazine protons).

EXAMPLE 42

1-[N-[2-(2,2,2-trifluoroethoxy)phenyl]-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

A mixture of 0.41 g of the compound described in example 41, 5.4 mL of 97% DIPEA, 3.9 mL of cyclohexanecarbonyl chloride in 30 mL of toluene was stirred at reflux for 10 h. After cooling to room temperature, the mixture was washed in the sequence with H₂O, 1 N NaOH and H₂O, the organic layer was dried on anhydrous Na₂SO₄ and evaporated to dryness. The crude was purified by flash chromatography (petroleum ether-EtOAc 1:1) followed by crystallization from Et₂O to give 0.2 g (37%) of the title compound. Melting point: 109.6-112° C.

¹H-NMR (CDCl₃, δ): 7.42-7.22 (m, 2H, trifluoroethoxyphenyl ring CHs), 7.15-6.77 (m, 6H, trifluoroethoxyphenyl ring CHs and methoxyphenyl ring CHs), 4.38 (q, 2H, OCH₂CF₃), 4.22-402 (m, 1H, CONCH(H)CH₂N), 3.82 (s, 3H, OCH₃), 3.58-3.39 (m, 1H, CONCH(H)CH₂N),3.15-2.90 (m, 4H, piperazine protons), 2.80-2.45 (m, 6H, CONCH₂CHN and piperazine protons), 2.05-1.88 (m, 1H, CHC(O)), 1.75-0.80 (m, 10H, cyclohexyl protons).

EXAMPLE 43

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine Hydrochloride

Preparation of N-(2-cyanophenyl)cyclohexanecarboxamide (Compound 43A)

This compound was prepared following the procedure described for compound 26A in example 26, except that 2-cyanoaniline was used in place of 2-trifluoromethylaniline. Yield 75%. M.p. 135-137° C.

¹H-NMR (CDCl₃, δ): 8.40 (dd, 1H, cyanophenyl ring H3), 7.70-7.50 (m, 3H, cyanophenyl ring H5 and H6 and NH), 7.12 (ddd, 1H, cyanophenyl ring H4), 2.30 (tt, 1H, CHC(O)), 2.05-1.10 (m, 10H, cyclohexyl protons).

Preparation of 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine Hydrochloride

The title compound was prepared following the procedure described for compound in example 39, except that compound 42A was used in place of compound 39A and reflux lasted 1 h. The crude was purified by flash chromatography (CH₂Cl₂-MeOH 98.2). The residue was dissolved in Me₂CO, added with HCl in Et₂O, evaporated to dryness, and crystallized from Me₂CO+Et₂O to give the title compound. Yield 7%.

¹H-NMR(DMSO-d₆, δ). 11.28-11.07 (br, 1H, NH⁺), 8.05 (dd, 1H, cyanophenyl ring H6), 7.92-7.80 (m, 2H, cyanophenyl ring CHs), 7.72-7.60 (m, 1H, cyanophenyl ring CH), 7.05-6.82 (m, 4H, methoxyphenyl ring CHs), 4.45-4.30 (m, 1H, CONCH(H)CH₂N), 3.92-3.75 (m, 1H, CONCH(H)CH₂N), 3.80 (s, 3H, OCH₃), 3.70-3.40 (m, 4H, piperazine protons), 3.40-3.00 (m, 6H, CONCH₂CH ₂N and piperazine protons), 1.98-1.80 (m, 1H, CHC(O)), 1.80-0.75 (m, 10H, cyclohexyl protons).

EXAMPLE 44

1-[N-(2-nitrophenyl)-1-amino-2-propyl]-4-(2-methoxyphenyl)piperazine

Preparation of 2-[4-(2-methoxyphenyl)-1-piperazinyl]propionamide (Compound 44A)

A mixture of 1 g of 1-(2-methoxyphenyl)piperazine, 0.57 g of 2-chloropropionamide, 1 mL of DIPEA and 5 mL of toluene was stirred at reflux for 3 h under N₂. After cooling to room temperature the mixture was poured into H₂O, extracted with EtOAc, then the organic layer was dried on Na₂SO₄ and the solvents evaporated to dryness. The residue was purified by flash chromatography (CH₂Cl₂-2 N methanolic ammonia 95:5) to give 0.88 g (63%) of compound 44A.

¹H-NMR (CDCl₃, δ): 7.25-7.10 (br, 1H, CONH(H)), 7.10-6.80 (m, 4H, methoxyphenyl ring CHs), 5.75-5.60 (br, 1H, CONH(H)), 3.85 (s, 3H,OCH₃), 3.20-3.00 (m, 4H, piperazine protons, NCH(CH₃)CO), 2.85-2.60 (m, 4H, piperazine protons), 1.30 (d, 3H, NCH(CH ₃)CO).

Preparation of 2-[4-(2-methoxyphenyl)-1-piperazinyl]propanamine (Compound 44B)

To a solution of 0.28 g of compound 44A in 7 mL of THF stirred at −4° C. under N₂ was added dropwise 2 mL of a 2 M THF solution of diborane dimethylsulfide. The mixture was refluxed for 6.5 h then 3 mL oh MeOH was added and the solvents evaporated to dryness. The residue was treated with water and extracted with EtOAc, the organic phase dried on Na₂SO₄ and evaporated to dryness. the residue was purified by flash chromatography (CH₂Cl₂-2 N methanolic ammonia 95:5) to give 0.07 g (24%) of compound 44B.

¹H-NMR(CDCl₃, δ): 7.10-6.80 (m, 4H, methoxyphenyl ring CHs), 3.85 (s, 3H,OCH₃), 3.20-2.90 (m, 4H, piperazine protons), 2.85-2.50 (m, 7H, piperazine protons and NCH(CH₃)CH ₂), 2.05-1.85 (br, 2H, NH₂), 0.95 (d, 3H, CH₃).

Preparation of 1-[N-(2-nitrophenyl)-1-amino-2-propyl]-4-(2-methoxyphenyl)piperazine

A mixture of 0.08 g of compound 44B, 0.03 mL of 2-nitrofluorobenzene, 0.3 mL of DIPEA and 5 mL of DMF was stirred at 140° C. for 3 h under N₂. The cooled mixture was diluted with water and extracted with diethyl ether; the organic phase was dried on Na₂SO₄, evaporated to dryness and the residue purified by flash chromatography (petroleum ether -EtOAc 8:2) to give 0.07 g (62%) of the title compound.

¹H-NMR (CDCl₃, δ): 8.90-8.70 (br, 1H, NH), 8.15 (dd, 1H, nitrophenyl ring H3), 7.40 (ddd, 1H, nitrophenyl ring H5), 7.15-6.70 (m, 5H, nitrophenyl ring H6 and methoxyphenyl ring CHs), 6.63 (ddd, 1H, nitrophenyl ring H4), 3.85 (s, 3H, OCH₃), 3.70-2.60 (m, 11H, piperazine protons and NHCH ₂CH(CH₃)), 1.10 (d, 3H, CH₃).

EXAMPLE 45

1-[N-(2-nitrophenyl)-N-cyclohexylcarbonyl-1-amino-2-propyl]-4-(2methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 4, except that the compound in example 44 was used in place of the compound in example 3, toluene was used instead of 1,2-dichloroethane and reflux lasted 13 h. The mixture was purified by flash chromatography (petroleum ether-EtOAc 1:1). Yield: 61%.

¹H-NMR (CDCl₃, δ): 8.05 (dd, 1H, nitrophenyl ring H3), 7.85-7.45 (m, 3H, nitrophenyl ring H4, H5 and H6), 7.10-6.75 (m, 4H, methoxyphenyl ring CHs), 3.85 (s, 3H, OCH₃), 3.90-3.75 (m, 1H, CONCH(H)CH(CH₃)), 3.65-2.30 (m, 10H, piperazine protons and CONCH(H)CHCH(CH₃)), 2.10-1.80 (m, 1H, CHC(O)), 1.80-0.80 (m, 13H, cyclohexyl protons and CH₃).

EXAMPLE 46

1-[N-cyclohexylcarbonyl-N-(2-methanesulphonylaminophenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

To a solution of 0.22 g of the compound of example 27 and 0.08 mL of triethylamine (TEA) in 5 mL of CH₂Cl₂, stirred at r.t. under anhydrous nitrogen atmosphere, was added dropwise a solution of 0.04 mL of methanesulphonyl chloride in 0.5 mL of CH₂Cl₂. The solution was stirred for 6 h at room temperature, afterwards, it was evaporated to dryness in vacuo and the residue was purified by flash chromatography (CH₂Cl₂-MeCN 9:1) affording 0.10 g (39%) of the title compound.

¹H-NMR (CDCl₃, δ): 9.55 (s, 1H, NH), 7.60 (dd, 1H, methanesulphonylaminophenyl ring CH), 7.30-7.45 (m, 1H, methanesulphonylaminophenyl ring CH), 7.10-7.23 (m, 2H, methanesulphonylaminophenyl ring CHs), 6.80-7.05 (m, 4H, methoxyphenyl ring ring CHs), 4.90-5.10 (m, 1H, CONCH(H)CH₂), 3.83 (s, 3H, OCH₃), 2.35-3.60 (m, 11H, piperazine protons, CONCH(H)CH₂), 3.05 (s, 3H, SO₂CH₃), 0.70-2.20 (m, 11H, cyclohexyl protons).

EXAMPLE 47

1-[N-(2-methoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine

The title compound was prepared according to the procedure described for compound in example 12, except that N-(2-chloroethyl)-2-methoxyaniline (prepared as described in J. Med. Chem. 1965, 8(3), 356-367), was used instead of N-(2-chloroethyl)-2-nitroaniline and DIPEA was used in place of TEA. The mixture was heated at 100-105° C. for 22 h and purified by flash chromatography (petroleum ether-EtOAc 70:30). Yield: 46%

¹H-NMR (CDCl₃, δ): 8.30 (bs, 1H, indolyl NH), 7.02-7.20 (m, 3H, indolyl H2, H5 and H6), 6.90 (ddd, 1H, methoxyphenyl ring H4 (H5)), 6.78 (ddd, 1H, methoxyphenyl ring H5 (H4)), 6.55-6.70 (m, 3H, indolyl H7, methoxyphenyl ring H3 and H6), 6.52 (dd, 1H, indolyl H3), 4.60-5.50 (br, 1, NHCH₂), 3.85 (s, 3H, CH₃O), 3.18-3.45 (m, 6H, HNCH ₂CH₂, 4 piperazine protons) 2.70-3.05 (m, 6H, HNCH₂CH ₂, 4 piperazine protons).

EXAMPLE 48

1-[N-cyclohexylcarbonyl-N-(2-methoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine

The title compound was synthetized as described for the compound of example 42 but substituting the compound of example 47 for the compound of example 41 and refluxing for 17 h. The crude was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 10:1.5). Yield: 62%.

¹H-NMR(CDCl₃, δ): 8.28(bs, 1H, NH),6.90-7.40(m,7H, methoxyphenyl ring CHs, indolyl H2, H5 and H6), 6.55-6.65 (m, 1H, indolyl H7), 6.50 (dd, 1H, indolyl H3), 4.10-4.30 (m, 1H, CONCH(H)), 3.83 (s, 3H, CH₃O), 3.10-3.75 (m, 5H, CONCH(H), piperazine protons), 2.45-3.10 (m, 6H, CONCH₂CH ₂, piperazine protons), 1.95-2.15 (m, 1H, CHCO), 0.80-1.75 (m, 10H, cyclohexyl protons)

By conventional methods the following salt of compound of example 48 was prepared: monohydrochloride m.p. 229-231° C.

EXAMPLE 49

1-[N-cyclohexylcarbonyl-N-(2-benzyloxycarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-carboxyphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine Hydrochloride Dihydrate (Compound 49A)

A solution of 0.33 g of the compound of example 18 and 0.06 g of lithium hydroxide monohydrate in 5 mL of THF and 1 mL of H₂O was stirred at 70° C. for 9 h. The solution was added with 2 N aq. HCl to pH≡1 and evaporated to dryness. The residue was taken up with 10 mL of boiling Me₂CO and filtered to give 0.32 g (84%) of the title compound as a white solid.

M.p. 169-171° C.

¹H-NMR(DMSO-d₆): 11.00-11.25 (br, 1H, CO₂H), 8.03 (dd, 1H,carboxyphenyl ring H6), 7.70 (t, 1H, carboxyphenyl ring H4), 7.50-7.65 (m, 2H, carboxyphenyl ring H3, H5), 6.80-7.07 (m, 4H, methoxyphenyl ring CHs), 4.50-5.30 (br, 5H, 2 H₂O and NH⁺), 4.15-4.35 (m, 1H, CONCH(H)CH₂), 3.75 (s, 3H, OCH₃), 3.35-3.65 (m, 5H, CONCH(H)CH₂, piperazine protons), 2.95-3.35 (m, 6H, CONCH₂CH ₂, piperazine protons), 1.75-1.95 (m, 1H, CHCO), 0.65-1.70 (m, 10H, cyclohexyl protons)

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-benzyioxycarbonylphenyl)-2-aminoethyl]-4-(2 -methoxyphenyl)piperazine

A solution of 0.49 g of the lithium salt of compound 49A, 0.24 mL of benzyl chloride, 0.35 mL of DIPEA and 4 mL of DMF was stirred at 100° C. for 13 h. The cooled mixture was then poured into 20 mL of H₂O and extracted with EtOAc (3×10 mL). The organic layer, dried on anhydrous Na₂SO₄ and evaporated to dryness gave a residue, which was purified by flash chromatography (CH₂Cl₂-MeOH 97:3) to afford 0.08 g (13%) of the title compound.

¹H-NMR (CDCl₃, δ): 8.00 (δδ, 1H,benzyloxycarbonylphenyl ring H3), 7.55 (dt, 1H, benzyloxycarbonylphenyl ring H5), 7.30-7.50 (m, 7H, benzyloxycarbonylphenyl ring H4, H6 and phenyl ring CHs), 6.80-7.10 (m, 4H, methoxyphenyl ring CHs), 5.35 and 5.25 (2d, 2H, CH ₂C₆H₅), 4.15-4.35 (m, 1H, CONCH(H)CH₂), 3.85 (s, 3H, OCH₃), 2.90-3.30 (m, 5H, CONCH(H)CH₂, 4 piperazine protons), 2.90 and 2.95 (2s, 1.2H, DMF CH₃s), 2.40-2.80 (m, 6H, CONCH₂CH ₂, 4 piperazine protons), 1.80-2.05 (m, 1H,CHCO), 0.75-1.80 (m, 10H, cyclohexyl protons).

EXAMPLE 50

1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine

Preparation of N-(2-hydroxyethyl)-2-trifluoromethoxyaniline (Compound 50A)

A stirred mixture of 5.64 g of 97% 2-trifluoromethoxyaniline and 3.4 mL of 97% 2-bromoethanol was heated at 115° C. for 8 h. After cooling to r.t., 50 ml, of CH₂Cl₂ was added and the solution was washed with 20% aq. sodium carbonate and H2O (3×20 mL), dried (anhydrous Na₂SO₄) and evaporated to dryness in vacuo. The residue was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 100:0.5) affording 3.18 g (46.5%) of the title compound as a yellow oil.

¹H-NMR (CDCl₃, δ): 7.08-7.25 (m, 2H, H3 and H4(5)), 6.90 (dd, 1H6), 6.75 (ddd, 1H H5(4)), 3.85 (t, 2H, CHOH), 3.35 (t, 2H, HNCH ₂), 0.80-3.20 (br, 2H, NH, OH).

Preparation of N-(2-chloroethyl)-2-trifluoromethoxyaniline (Compound 50B)

A stirred mixture of2.51 g of compound 50A, 6.15 g of 99% triphenylphosphine, 50 mL of carbon tetrachloride and 50 mL of CHCl₃ was heated at reflux for 8 h. The solution was evaporated to dryness in vacuo and the residue was purified by flash chromatography to afford 2.26 g (83.5%) of the title compound as a yellow oil.

¹H-NMR (CDCl₃, δ): 7.08-7.25 (m, 2H, aromatic CHs), 6.62-6.81 (m, 2H, aromatic CHs), 3.85-4.75 (br, 1H, NH), 3.63-3.78 (m, 2H, CH₂Cl), 3.48-3.62 (m, 2H, CH ₂NH).

Preparation of 1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine

The title compound was prepared according to the procedure described for compound in example 12, except that compound 50B was used instead of N-(2-chloroethyl)-2-nitroaniline and DIPEA was used in place of triethylamine. The mixture was heated at 110° C. for 8 h and purified by flash chromatography (petroleum ether-EtOAc 70:30) to afford the title compound. Yield: 42.5%

¹H-NMR (CDCl₃, δ): 8.18 (bs, 1H, indolyl NH), 7.05-7.25 (m, 5H, indolyl H2, H5 and H6, trifluoromethoxyphenyl ring CHs), 6.58-6.85 (m, 3H, indolyl H7, trifluoromethoxyphenyl ring CHs), 6.45-6.50 (m, 1H, indolyl H3), 4.92 (bs, 1H, CH₂NH), 3.20-3.55 (m, 6H, NHCH ₂CH ₂, piperazine protons), 2.65-3.05 (m, 6H, NHCH₂CH ₂, piperazine protons).

EXAMPLE 51

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine

The title compound was synthetized as described for example 42 but substituting the compound of example 50 for the compound of example 41 and stirring at room temperature for 15 h. The crude was purified by flash chromatography (petroleum ether-EtOAc 70:30). Yield: 56%.

¹H-NMR (CDCl₃, δ): 8.25 (s, 1H,indolyl NH), 7.02-7.55 (m, 7H, indolyl H2, H5 and H6, trifluoromethoxyphenyl ring CHs), 6.45-6.65 (m, 2H, indolyl H3 and H7), 4.25-4.45 (m, 1H CONCH(H)CH₂), 3.05-3.70 (m, 5H, CONCH(H)CH₂, piperazine protons), 2.35-3.05 (m, 6H, CONCH(H)CH ₂, piperazine protons), 1.85-2.10 (m, 1H, CHCO), 0.75-1.60 (m, 10H, cyclohexyl protons).

EXAMPLE 52

1-[N-(2-nitrophenyl)-2-aminopropyl]-4-(2-methoxyphenyl)piperazine

The title compound was prepared according to the procedure reported for the synthesis of the compound of example 44 but substituting 1-[4-(2-methoxyphenyl)-1-piperazinyl]propan-2-amine (EP 512,755; EP 395,313) for compound 44B and heating for 1.5 h. The residue was purified by flash chromatography (CH₂Cl₂-MeOH 9:1). Yield: 80%.

¹H-NMR (CDCl₃, δ): 8.25-8.43 (br, 1H, NH), 8.20 (dd, 1H, nitrophenyl ring H3), 7.40 (t, 1H nitrophenyl ring H5), 6.80-7.05 (m, 5H, nitrophenyl ring H6 and methoxyphenyl ring CHs), 6.63 (t, 1H,nitrophenyl ring H4), 3.85 (s, 3H, OCH₃), 3.70-3.90 (m, 1H, C ₂C(H)CH₃), 3.00-3.17 and 2.50-2.83 (2m, 10H, piperazine protons and CH ₂C(H)CH₃, 1.33 (d, 3H, CH₂C(H)CH ₃),

EXAMPLE 53

1-[N-(2-nitrophenyl)-N-(2-pyrazinecarbonyl)-2-aminoethyl)]-4-(4-indolyl)piperazine

The title compound was prepared following the procedure described for the compound in example 32, except that 2-pyrazinecarbonyl chloride was used in place of 3-furylcarbonyl chloride and the compound of example 12 was used instead of that of example 1 and reflux lasted 3 h. The crude was purified by flash chromatography (petroleum ether-EtOAc 80:20, EtOAc, EtOAc-MeOH 98:2). Yield: 8%.

¹H-NMR (CDCl₃, δ): 9.12 (d, 1H, pyrazine H3), 8.43 (d, 1H, pyrazine H6), 8.25(bs, 1H, NH 8.05 (δδ, 1H, pyrazine H5), 7.95 (δδ, 1H, nitrophenyl ring H3), 7.50-7.70 (m, 2H, nitrophenyl ring H6 and H5 (4)), 7.32-7.50 (m, 1H, nitrophenyl ring H4 (5)), 7.02-7.25 (m, 3H, indoyl H2, H5, H6), 5.42-6.65 (m, 2H, indolyl H7, H3), 3.95-4.50 (m, 2H, CONCH ₂CH₂), 2.40-3.50 (m, 10H, CONCH₂CH ₂, piperazine protons).

EXAMPLE 54

1[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)-piperazine

The title compound was synthetized by reacting compound 50B and 1-(2-methoxy-4-nitrophenyl)piperazine (prepared as described in WO 95/17831) instead of 1-(4-indolyl)piperazine, following the procedure described for the compound of example 50 and heating at 120° C. for 13 h. The residue was purified by flash chromatography (petroleum ether-EtOAc 70:30). Yield: 57%.

¹H-NMR (CDCl₃, δ): 7.88 (dd, 1H,methoxyphenyl ring H5), 7.72 (d, 1H, methoxyphenyl ring, H3), 7.09-7.22 (m, 2H, trifluoromethoxyphenyl ring H3 and H5), 6.90 (d, 1H, methoxyphenyl ring H6), 6.60-6.80 (m, 2H, trifluoromethoxyphenyl ring H4 and H6), 4.90 (bs, 1H, NH), 3.95 (s, 3H, OCH₃), 3.10-3.45 (m, 6H, HNCH ₂CH₂, piperazine protons), 2.55-2.90 (m, 6HNCH₂CH ₂, piperazine protons).

EXAMPLE 55

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-⁴-(2-methoxy-4-nitrophenyl)piperazine

A mixture of 0.855 g of compound of example 54, 0.84 mL of 97% TEA, 0.70 mL of 98% cyclohexanecarbonyl chloride and 40 mL of CH₂Cl₂ was maintained at 20-25° C. for 24 h. The solution was washed with H₂O (4×10 mL), 1 N NaOH (4×10 mL), H₂O (4×10 mL), dried (anhydrous Na₂SO₄) and evaporated to dryness in vacuo. The residue was purified by flash chromatography (petroleum ether-EtOAc 70:30) to afford 0.841 g (79%) of the title compound.

¹H-NMR (CDCl₃, δ): 7.85 (dd, 1H, nitrophenyl ring H5), 7.68 (d, 1H, nitrophenyl ring H3), 7.26-7.50 (m, 4H, trifluoromethoxyphenyl ring CHs), 6.85 (d, 1H, nitrophenyl ring H6), 4.20-4.40 (m, 1H, CONCH(H)CH₂), 3.92 (s, 3H, CH₃O), 3.08-3.40 (m, 5H, CONCH(H)CH₂, piperazine protons), 2.45-2.80 (m, 6H, CONCH(H)CH ₂, piperazine protons), 1.85-2.05 (m, 1H,CHCO), 0.75-1.75 (m, 10H, cyclohexyl protons).

EXAMPLE 56

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-amino-2-methoxyphenyl)piperazine

The title compound was prepared according to the procedure reported in example 27, but substituting the compound of example 55 for the compound of example 2 and heating at reflux for 3 h. The residue was purified by flash chromatography (EtOAc). Yield: 58%.

¹H-NMR (CDCl₃, δ): 7.25-7.54 (m, 4H, trifluoromethoxyphenyl ring CHs), 6.75 (d, 1H aminophenyl ring H6), 6.18-6.30 (m, 2H, aminophenyl ring H3 and H5), 4.20-4.40 (m, 1H, CONCH(H)CH₂), 3.78 (s, 3H, CH₃O ), 3.50 (bs, 2H, NH₂), 3.15-3.38 (m, 1H, CONCH(H)CH₂), 2.80-3.15 (m, 4H, piperazine protons), 2.40-2.75 (m, 6H, piperazine protons, CONCH(H)CH ₂), 1.85-2.05 (m, 1H, CHCO), 0.80-1.75 (m, 10H, cyclohexyl protons).

EXAMPLE 57

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-acetylamino-2-methoxyphenyl)piperazine

The title compound was synthesized according to the procedure reported in example 28 but substituting the compound of example 56 for the compound of example 27 and stirring for 20 h. The residue was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 100:3) affording the title compound as a vitreous pink solid. Yield: 77%.

¹H-NMR (CDCl₃, δ): 7.25-7.52 (m, 5H, trifluoromethoxyphenyl ring CHs and methoxyphenyl ring CH), 7.18 (s, 1H, NHCO), 6.82 (s, 2H, methoxyphenyl ring CHs), 4.22-4.42 (m, 1H, CONCH(H)CH₂), 3.85 (s, 3H, CH₃O), 3.17-3.40 (m, 1H, CONCH(H)CH₂), 2.85-3.10 (m, 4H, piperazine protons), 2.40-3.10 (m, 6H, piperazine protons, CONCH(H)CH ₂), 2.15 (s, 3H, CH₃CO), 1.85-2.05 (m, 1H, CHCO), 0.75-1.75 (m, 10H, cyclohexyl protons)

EXAMPLE 58

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-trifluoroacetylamino-2-methoxyphenyl)piperazine

The title compound was synthesized according to the procedure reported in example 28 but substituting the compound of example 56 for the compound of example 27 and trifluoroacetic anhydride for acetyl chloride and stirring for 20 h. The residue was purified by flash chromatography (EtOAc-petroleum ether 6:4). Yield: 64%.

¹H-NMR (DMSO-d₆, δ): 11.10 (s, 1H, NH), 7.40-7.65 (m, 4H, trifluoromethoxyphenyl ring CHs), 7.35 (d, 1H, methoxyphenyl ring H6), 7.25 (s, 1H, methoxyphenyl ring H3), 7.20 (dd, 1H, methoxyphenyl ring H5), 4.05-4.10 (m, 1H, CONCH(H)CH₂), 3.75 (s, 3H, CH₃O), 3.10-3.30 (m, 1H, CONCH(H)CH₂), 2.80-3.00 (m, 4H, piperazine protons), 2.30-2.60 (m, 6H, piperazine protons, CONCH(H)CH ₂), 1.85-2.00 (m, 1H, CHCO), 0.75-1.80 (m, 10H, cyclohexyl protons)

EXAMPLE 59

1-[N-cyclohexylcarbonyl-N-(2-propoxycarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

A mixture of 0.17 g of the compound 49A of example 49, 0.14 g of anhydrous potassium carbonate, 0.2 mL of 1-bromopropane and 3 ml, of DMF was stirred at 60° C. under nitrogen atmosphere for 6 h. The cooled mixture was filtered, poured into 50 mL of H₂O and extracted with EtOAc. The organic layer, dried on anhydrous Na₂SO₄, was evaporated to dryness to give 0.10 g (62%) of the title compound.

¹H-NMR (CDCl₃, δ): 7.95-8.05 (m, 1H, phenyl ring H3), 7.57 (dt, 1H, phenyl ring H4), 7.35-7.50(m, 2H, phenyl ring H3, H6), 6.80-7.05 (m, 4H, methoxyphenyl ring CHs), 4.25-4.50 (m, 1H, CONCH(H)CH₂), 4.20 (dt, 2H, CO₂CH ₂CH₂CH₃), 3.85 (s, 3H, OCH₃), 2.40-3.40 (m, 11H, CONCH(H)CH₂, piperazine protons), 1.80-2.00 (m, 1H, CHCO), 1.65-1.85 (m, 2H, CO₂CH₂CH ₂CH₃), 1.00 (t, 3H, CO₂CH₂CH₂CH ₃), 0.80-1.80 (m, 10H, cyclohexyl protons)

EXAMPLE 60

1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-(N-acetyl-N-cyclohexylcarbonyl)amino-2-methoxyphenyl]piperazine

Preparation of 1-[N-(2-nitrophenyl)-2-aminoethyl]-(4-amino-2-methoxyphenyl)piperazine (Compound 60A)

The title compound was prepared according to the procedure described for compound in example 12, except that 1-(4-amino-2-methoxyphenyl)piperazine was used instead of 1-(4-indolyl)piperazine and DIPEA was used in place of triethylamine. The mixture was heated at 90° C. for 16 h and purified by flash chromatography (EtOAc-3 N methanolic NH₃ 98:2) to afford the title compound. Yield: 34%.

¹H-NMR (CDCl₃, δ): 8.40 (bs, 1H, NH), 8.18 (d, 1H, nitrophenyl ring H3), 7.45 (dd, 1H, nitrophenyl ring H5), 6.81-6.95 (m, 2H, nitrophenyl ring H2 and methoxyphenyl ring H6), 6.60 (dd, 1H, nitrophenyl ring H4), 6.20-6.31 (m, 2H, methoxyphenyl ring H3, H5), 3.80 (s, 3H, CH₃O), 3.29-3.52 (m, 2H, NHCH ₂), 2.50-4.00 (m, 2H, NH₂), 2.90-3.20 (m, 4H, piperazine protons), 2.58-2.90 (m, 6H, piperazine protons, NHCH₂CH ₂N).

Preparation of 1-[N-(2-nitrophenyl)-2-aminoethyl]-4-(4-acetylamino-2-methoxyphenyl)piperazine (Compound 60B)

The title compound was synthesized according to the procedure reported in example 28 but substituting compound 60A for the compound of example 27, CHCl₃ for CH₂Cl₂ and stirring for 3 h. Usual work-up followed by evaporation of the solvent afforded compound 60B. Yield: 99%.

¹H-NMR (CDCl₃, δ): 8.40 (bs, 1H, NHCO), 8.18 (d, 1H, nitrophenyl ring H3), 7.40-7.52 (m, 2H, nitrophenyl ring H5 and H6 (or methoxyphenyl ring H3)), 7.20 (bs, 1H, NHCH₂), 6.70-6.97 (m, 3H, methoxyphenyl ring H6 and H3 (or nitrophenyl ring H6) and nitrophenyl ring H4), 6.64 (dd, 1H, methoxyphenyl ring H5), 3.85 (s, 3H, OCH₃), 3.34-3.58 (m, 2H, NHCH ₂CH₂N), 2.95-3.20 (m, 4H, piperazine protons), 2.62-2.95 (m, 6H, piperazine protons and NHCH₂CH ₂N), 2.15 (s, 3H, CH₃CO).

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-(N-acetyl-N-cyclohexylcarbonyl)amino-2-methoxyphenyl]piperazine

The title compound was synthesized following the procedure described for the compound in example 42, except that compound 60B was used instead of that of example 41 and reflux lasted 2 h. The crude was purified by flash chromatography (EtOAc-petroleum ether 9:1). Yield: 27%.

¹H-NMR (CDCl₃, δ): 8.05 (dd, 1H, nitrophenyl ring H3), 7.42-7.73 (m, 3H, nitrophenyl ring H4, H5 and H6), 6.91 (d, 1H, methoxyphenyl ring H6), 6.68 (dd, 1H, methoxyphenyl ring H5), 6.55 (d, 1H, methoxyphenyl ring H3), 3.55-4.18 (m, 5H, CH₃O and CONCH ₂CH₂N), 2.37-3.21 (m, 10H, piperazine protons and CONCH₂CH ₂N), 2.35 (s, 3H, CH₃CO), 0.72-2.05 (m, 22H, cyclohexyl protons).

EXAMPLE 61

1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-(bis-cyclohexylcarbonyl)amino-2-methoxyphenyl]piperazine

Preparation of 1-[N-(2-nitrophenyl)-2-aminoethyl]-4-(4-tritylamino-2-methoxyphe-nyl)piperazine (Compound 61A)

A solution of compound 60A (0.806 g), triphenylmethyl chloride (0.60 g) and TEA (0.33 mL) in CHCl₃ (20 mL) was stirred at r.t. for 8 h, and poured into 0.1 N NaOH (500 mL). The aqueous phase was extracted with CHCl₃ (3×50 mL,) and the combined organic phases were washed with H₂O, dried (Na₂SO₄) and the solvent evaporated under vacuum. The crude was purified by flash chromatography (EtOAc-petroleum ether 6:4) to give 1.01 g (76%) of the title compound.

¹H-NMR (CDCl₃, δ): 8.45 (bs, 1H, NH), 8.21 (d, 1H, nitrophenyl ring H3), 7.47 (dd, 1H, nitrophenyl ring H5), 7.11-7.38 (m, 16H, triphenylmetane and nitrophenyl ring H6), 6.80-6.99 (m, 1H, methoxyphenyl ring H6), 6.55-6.72 (m, 2H, nitrophenyl ring H4 and NH), 6.00 (dd, 1H, methoxyphenyl ring H5), 5.83 (d, 1H, methoxyphenyl ring H3), 3.31-3.58 (m, 5H, NHCH ₂CH₂N and CH₃O), 2.58-3.23 (m, 10H, piperazine protons and NHCH₂CH ₂N).

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-(bis-cyclohexylcarbonyl)amino-2-methoxyphenyl]piperazine

The title compound was synthesized following the procedure described for the compound in example 42, except that compound 61A was used instead of that of example 41 and reflux lasted 5 h. The crude was purified twice by flash chromatography (EtOAc-petroleum ether gradient from 4:6 to 8:2 followed by EtOAc-petroleum ether 4:6). Yield: 21%.

¹H-NMR (CDCl₃, δ): 8.08 (d, 1H, nitrophenyl ring H3), 7.42-7.75 (m, 3H, nitrophenyl ring H4, H5 and H6), 6.91 (d, 1H,methoxyphenyl ring H6), 6.63 (dd, 1H, methoxyphenyl ring H5), 6.51 (d, 1H, methoxyphenyl ring H3), 3.51-4.15 (m, 5H, CH₃O and CONCH ₂CH₂N), 2.18-3.25 (m,13H, cyclohexyl CHCO, piperazine protons and CONCH₂CH ₂N), 0.72-2.10 (m, 30H, cyclohexyl protons).

EXAMPLE 62

1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-cyclohexanecarbonylamino-2-methoxyphenyl)piperazine

The title compound was obtained as a by-product during the synthesis of the compound of example 61. Repurification by flash chromatography (EtOAc-petroleum ether 9:1) gave the title compound. Yield: 20%.

¹H-NMR (CDCl₃, δ): 8.08 (d, 1H, nitrophenyl ring H3), 7.45-7.80 (m, 4H, aromatic CHs), 7.35-7.45 (m, 2H, aromatic CHs), 7.10 (br, 1H, NH), 3.55-4.25 (m, 5H, CH₃O and CONCH ₂CH₂N), 2.30-3.25 (m, 10H, piperazine protons and CONCH₂CH ₂N), 2.20 (tt, 2H, CHCO), 0.72-2.10 (m, 20H, cyclohexyl protons).

EXAMPLE 63

1-[N-(2-nitrophenyl)-N-(2-pyrimidinecarbonyl)-2-aminoethyl)]-4-(2-methoxyphenyl)piperazine

Preparation of 2-pyrimidinecarbonyl Chloride (Compound 62A)

A stirred mixture of 0.837 g of 2-pyrimidinecarboxylic acid hydrochloride (prepared as described in S. Gronowitz et al. Ark. Chem, 1964, 22, 66-82), 30 mL of CHCl₃ and 2 mL of thionyl chloride was heated at reflux for 12 h. After cooling to r.t., the suspension was filtered and the filtrate was evaporated to dryness in vacuo to afford 0.306 g (67%) of the title compound as a green solid used in the next step without further purification.

Preparation of 1-[N-(2-nitrophenyl)-N-(2-pyrimidinecarbonyl)-2-aminoethyl)]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 32, except that compound 61A was used in place of 3-furylcarbonyl chloride and reflux lasted 11 h. The crude was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 100:3). Yield: 65%.

¹H-NMR (DMSO-d₆, δ): 9.00 and 8.60 (2d, 2H, pyrimidine H4 and H6), 8.10 and 7.98 (2dd, 1H, nitrophenyl ring H3), 7.90-7.78 and 7.70-7.52 (2m, 2H, nitrophenyl ring H5 and H6), 7.52-7.43 (m, 1H, nitrophenyl ring H4), 7.32 (t, 1H, pyrimidine H5), 7.00-6.65 (m, 4H, methoxyphenyl ring CHs), 4.45-4.22 and 4.12-3.80 (2m, 1H, CONCH(H)CH₂), 3.72 and 3.69 (2s, 3H, CH₃O), 2.15-2.95 (m, 11H, CONCH(H)CH ₂, piperazine protons)

EXAMPLE 64

1-[N-[2-(2,2,2-trifluoroethoxy)phenyl)]-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine

Preparation of N-(2-hydroxyethyl)-2-(2,2,2-trifluoroethoxy)aniline (Compound 64A)

The title compound was synthesized following the procedure described for compound 50A, but substituting 2-(2,2,2-trifluoroethoxy)aniline for 2-trifluoromethoxyaniline. Purification by flash chromatography (petroleum ether-EtOAc 80:20) afforded the title compound as a brown solid. Yield: 58%.

¹H-NMR (CDCl₃, δ): 6.96 (ddd, 1H, H4 (H5)), 6.62-6.85 (m, 3H, H5 (H4), H3 and H6), 4.38 (q, 2H, OCH₂CF₃), 3.85 (t, 2H, CH₂OH), 3.25-3.45 (m, 2H, NCH₂),2.20-4.50 (br, 1H, NH). The OH signal is not displayed.

Preparation of N-(2-chloroethyl)-2-(2,2,2-trifluoroethoxy)aniline (Compound 64B)

The title compound was synthesized following the procedure described for compound 50B, but substituting compound 64A for compound 50A. Purification by flash chromatography (CH₂Cl₂) afforded the title compound as a yellow oil. Yield: 89%.

¹H-NMR (CDCl₃, δ): 6.90-7.05 (m, 1H, H4 (H5)), 6.68-6.90 (m, 3H, H5 (H4), H3 and h6), 4.85-6.50 (br, 1H, NH), 4.40 (q, 2H, OCH₂CF₃), 3.65-3.80 (m, 2H, CH₂Cl), 3.48-3.65 (m, 2H, NCH₂).

Preparation of 1-[N-[2-(2,2,2-trifluoroethoxy)phenyl)]-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine

The title compound was prepared according to the procedure described for compound in example 50, except that Compound 64B was used instead of compound 50B and 1-(2-metossi-4-nitrophenyl)piperazine instead of 1-(4-indolyl)piperazine. The mixture was heated at 115° C. for 8 h and purified by flash chromatography (petroleum ether-EtOAc 80:20). Yield: 55%

¹H-NMR (CDCl₃, δ): 7.88 (dd, 1H, methoxyphenyl H5), 7.70 (d, 1H, methoxyphenyl H3), 6.96 (ddd, 1H, trifluoroethoxyphenyl H5 (H4)), 6.90 (d, 1H, methoxyphenyl H6), 6.60-6.82 (m, 3H, trifluoroethoxyphenyl H4 (H5), H3, H6), 4.70-5.20 (m, 1H, NH), 4.37 (q, 2H, OCH₂CF₃), 3.95 (s, 3H, OCH₃), 3.10-3.40 (m, 6H, NHCH ₂CH₂, piperazine protons), 2.55-2.90 (m, 6H, NHCH₂CH ₂, piperazine protons).

EXAMPLE 65

1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(2-methoxy-4-nitrophenyl)piperazine

The title compound was synthetized as described for compound in example 55 but substituting the compound of example 64 for the compound of example 54. The crude was purified by flash chromatography (petroleum ether-EtOAc 1:1). Yield: 91%.

¹H-NMR (CDCl₃, δ): 7.87 (δδ, 1H, methoxyphenyl ring H5), 7.70 (d, 1H, methoxyphenyl ring, H3), 7.25-7.45 (m, 2H, trifluoroethoxyphenyl ring H5(4), methoxyphenyl ring H6), 7.10 (ddd, 1H, trifluoroethoxyphenyl ring H4(5)), 6.80-7.00 (m, 2H, trifluoroethoxyphenyl ring H3 and H6), 4.30-4.50 (m, 2H, OCH₂CF₃), 4.05-4.25 (m, 2H, CONCH(H)), 3.92 (s, 3H, CH₃O), 3.35-3.65 (m, 1H, CONCH(H)), 3.05-3.30 (m, 4H, piperazine protons), 2.40-2.85 (m, 6H, piperazine protons), CONCH₂CH ₂), 1.90-2.05 (m, 1H, CHCO), 0.80-1.25 (m, 10H, cyclohexyl protons).

EXAMPLE 66

1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(4-amino-2-methoxyphenyl)piperazine

The title compound was prepared according to the procedure reported in example 27, but substituting the compound of example 65 for the compound of example 2 and stirring at room temperature for 5 h. The catalyst was filtered off and washed with MeOH. Evaporation of the filtrate afforded the title compound. Yield: 93%.

¹H-NMR (DMSO-d₆,δd): 7.30-7.50 (m, 2H, trifluoroethoxyphenyl ring H4 and H6), 7.25 (dd, 1H, trifluoroethoxyphenyl ring H3), 7.10 (ddd, 1H, trifluoroethoxyphenyl ring H5), 6.55 (d, 1H, methoxyphenyl ring H6), 6.20 (d, 1H, methoxyphenyl ring H3), 6.05 (dd, 1H, methoxyphenyl ring H5), 4.50-5.00 (m, 4H, OCH₂CF₃, NH₂), 3.75-4.00 (m, 1H, CONCH(H)), 3.65 (s, 3H, CH₃O), 3.25-3.50 (m, 1H, CONCH(H)), 2.70 (br, 4H, piperazine protons), 2.20-2.50 (m, 6H, piperazine protons, CONCH₂CH ₂), 1.82-2.05 (m, 1H, CHCO), 0.70-1.70 (m, 10H, cyclohexyl protons).

EXAMPLE 67

1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(4-acetylamino-2-methoxyphenyl)piperazine

The title compound was synthesized according to the procedure reported in example 28 but substituting the compound of example 66 for the compound of example 27 and stirring at 20-25° C. for 5 h. After overnight resting, dilution with CH₂Cl₂, followed by the usual work-up afforded the title compound. Yield: 73%.

¹H-NMR (DMSO-δ6, δd): 9.25 (s, 1H,NHCO), 7.30-7.48 (m, 2H, trifluoroethoxyphenyl ring H4 and H6), 7.20-7.30 (m, 2H, trifluoroethoxyphenyl ring H3, methoxyphenyl ring H3), 7.10 (ddd, 1H, trifluoroethoxyphenyl ring H5), 7.00 (dd, 1H, methoxyphenyl ring H5), 5.75 (d, 1H, methoxyphenyl ring H6), 4.70-4.97 (m, 2H, OCH₂CF₃) 3.75-3.97, m, 1H, CONCH(H)), 7.70 (s, 3H, CH₃O), 3.25 -3.45 (m, 1H, CONCH(H)), 2.70-3.00 (m, 4H, piperazine protons), 2.25-2.55 (m, 6H, piperazine protons, CONCH₂CH2), 1.95 (s, 3H, COCH₃), 1.80-2.15 (m, 1H, CHCO), 0.70-1.65 (m, 10H, cyclohexyl protons)

EXAMPLE 68

1-[N-[2-(2,2,2-trifluoroethoxy)phenyl)]-2-aminoethyl]-4-(4-indolyl)piperazine

The title compound was synthesized following the procedure reported for compound of example 64 but substituting 1-(4-indolyl)piperazine for 1-(2-methoxy-4-nitrophenyl)piperazine. Purification by flash chromatography (CH₂Cl₂-2 N methanolic NH₃ 100:1.5) afforded the title compound as a white vitreous solid. Yield: 49%.

¹H-NMR (CDCl₃δ): 8.22 (bs, 1H, indolyl NH), 6.92-7.20 (m, 4H, trifluoroethoxyphenyl ring H4 (H5), indolyl H2, H7 and H6), 6.45-6.85 (m, 5H, trifluoroethoxyphenyl ring H3, H5 (H4) and H6, indolyl H3 and H5), 4.96 (bs, 1H, NH), 4.37 (q, 2H, OCH₂CF₃), 3.10-3.58 (m, 6H, HNCH ₂CH₂, piperazine protons), 2.40-3.10 (m, 6H, HNCH₂CH ₂, piperazine protons).

EXAMPLE 69

1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl ]-4-(4-indolyl)piperazine

The title compound was synthetized as described for example 51 but substituting the compound of example 68 for the compound of example 50. The crude was purified by flash chromatography (CH₂Cl₂-2 N methanolic NH₃ 100:3) affording the title compound as a vitreous ivory solid. Yield: 83%.

¹H-NMR (CDCl₃, δ): 8.26 (bs, 1H, indolyl NH), 7.22-7.45 (m, 2H, indolyl H2 and H7), 7.00-7.22 (m, 4H, indolyl H6, trifluoroethoxyphenyl ring H4, H5 and H6), 6.95 (dd, 1H trifluoroethoxyphenyl ring H3), 6.48-6.53 (m, 2H, indolyl H3 and H5), 4.42 (q, 2H, OCH₂CF₃), 4.02-4.25 (m, 1H, CONCH(H)), 3.40-3.70 (m, 1H, CONCH(H)), 3.12-3.35 (m, 4H, piperazine protons), 2.45-2.95 (m, 6H, piperazine protons, CONCH₂CH₂), 1.90-2.05 (m, 1H, CHCO), 0.75-1.80 (m, 10H, cyclohexyl protons).

EXAMPLE 70

1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl)]-4-(4-acetylamino-2-methoxyphenyl)piperazine

Preparation of 1-(4-amino-2-methoxyphenyl)piperazine (Compound 70A)

The title compound was synthesized following the method reported in example 27 but using 1-(2-methoxy-4-nitrophenyl)piperazine instead of the compound of example 2. After 4 h stirring and 2 days resting the catalyst was filtered off and the solvent was evaporated under vacuum. The crude was purified by flash chromatography (CH₂Cl₂-3 N methanolic NH₃ 9:1) to give the title compound. Yield: 64%.

¹H-NMR (CDCl₃, δ): 6.80 (d,1H6), 6.20-6.35 (m, 2H, H3 and H5), 3.87 (s,3H, CH₃), 3.50 (m, 3H, NH₂ and NH), 2.95-3.30 (m, 8H, piperazine protons).

Preparation of 1-(4-amino-2-methoxyphenyl)-4-tert-butoxycarbonylpiperazine (Compound 70B)

To a solution of compound 70A (3.18 g) in anhydrous THF (70 ml,) at 0° C. di-tert-butyl di-carbonate (3.17 g) was added. The resulting mixture was stirred at 0° C.-r.t. for 2 h, poured into brine (500 mL), alkalinized with 1 N NaOH and extracted with EtOAc (2×300 mL). The combined organic layers were washed with H₂O, dried (Na₂SO₄) and the solvent was evaporated under vacuum. The crude was purified by flash chromatography (EtOAc-petroleum ether 8:2) to give 2.6 g (55%) of the title compound.

¹H-NMR (CDCl₃, δ): 6.80 (d, 1H, H6), 6.20-6.35 (m, 2H, H3 and H5), 3.80-4.10 (br, 2H, NH₂) 3.86 (s, 3H, CH₃O), 3.55-3.65 (m, 4H, piperazine protons), 2.85-3.11 (m, 4H, piperazine protons), 1.47 (s, 9H, (CH₃)₃C).

Preparation of 1-tert-buthoxycarbonyl-4-[4-(1,3(2H)-dioxo-1H-1-isoindolyl)-2-methoxyphenyllpiperazine (Compound 70C)

A solution of the compound 70B (0.48 g), phthalic anhydride (0.26 g) and DIPEA (0.30 mL) in 1,2-DCE (15 mL) was stirred at reflux for 2 h. The solution was cooled to r.t., diluted with CHCl₃, washed with 0.5 N NaOH and H₂O, dried (Na₂SO4) and the solvents were evaporated under vacuum. The crude was purified by flash chromatography (EtOAc-petroleum ether 4:6) to give 0.24 g (35%) of the title compound.

¹H-NMR (CDCl₃, δ): 7.75-8.02 (m, 4H, isoindolyl CHs), 6.85-7.20 (m, 3H, phenyl ring CHs), 3.88 (s, 3H, CH₃O), 3.55-3.82 (m, 4H, piperazine protons), 2.91-3.35 (m, 4H, piperazine protons), 1.47 (s, 9H, (CH₃)₃C).

Preparation of 1-[4-(1,3(2H)-dioxo-1H-2-isoindolyl)-2-methoxyphenyl]piperazine (Compound 70D)

A solution of compound 70C. (0.23 g) and trifluoroacetic acid (0.38 mL) in CHCl₃ (10 ml,) was stirred at r.t. for 2 h, at 40° C. for 2 h and at 60° C. for 2 h. Additional trifluoroacetic acid (0.76 mL) was added. The solution was stirred at r.t. for 2 h, washed with 1 N NaOH (25 mL) and H₂H, dried (Na₂SO₄) and the solvents were evaporated under vacuum to give 0.14 g (80%) of the title compound.

¹H-NMR (CDCl₃, δ):), 7.75-8.02 (m, 4H, isoindolyl CHs), 6.95-7.10 (m, 2H, phenyl ring H5 and H6), 6.90 (s, 1H, phenyl ring H3), 3.30 (br, 1H, NH), 3.91 (s, 3H, CH₃O), 3.03-3.20 (m, 8H, piperazine protons).

Preparation of 1-[N-(2-nitrophenyl)-2-aminoethyl]-1-[4-(2,3-dihydro-1,3-dioxo-1H-2-isoindolyl)-2-methoxyphenyl]piperazine (Compound 70E)

The title compound was prepared as described for the compound of example 12, but using compound 70D instead of 1-(4-indolyl)piperazine and DIPEA instead of TEA and stirring at 90 ° C. for 16 h. Extraction with EtOAc (2×20 mL) followed by the usual work-up gave a crude which was purified by flash chromatography (EtOAc-petroleum ether 7:3) to afford the title compound. Yield: 33%.

¹H-NMR (DMSO-d₆, δ): 8.45 (bt, 1H, NH), 8.08 (d, 1H, nitrophenyl ring H3), 7.81-8.00 (m, 4H, isoindolyl CHs), 7.57 (dd, 1H, nitrophenyl ring H5), 6.90-7.12 (m, 4H, nitrophenyl ring H4 and methoxyphenyl ring CHs), 6.70 (dd, 1H, nitrophenyl ring H6), 3.77 (s, 3H, CH₃O), 3.38-3.52 (m, 2H, NHCH ₂CH₂N), 2.95-3.18 (m, 4H, piperazine protons), 2.52-2.80 (m, 6H, piperazine protons and NHCH₂CH ₂N).

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl)]-4-[4-(1,3(2H) -dioxo-1H-2-isoindolyl)-2-methoxyphenyl]piperazine (Compound 70F)

The title compound was obtained following the method of example 42 using compound 70E instead of compound 41 and stirring at reflux for 4 h. The crude was purified by flash chromatography (EtOAc-petroleum ether 8:2) to afford the title compound. Yield: 49%.

¹H-NMR (DMSO-d₆, δ): 8.17 (d, 1H, nitrophenyl ring H3), 7.61-8.01 (m, 7H, isoindol CHs and nitrophenyl ring H4, H5 and H6), 6.82-7.08 (m, 3H, methoxyphenyl ring CHs), 3.50-3.92 (m, 5H, CONCH ₂CH₂N and CH₃O), 2.65-2.96 (m, 4H, piperazine protons), 2.22-2.53 (m, 6H, piperazine protons and CONCH₂CH ₂N), 2.05-2.19 (m, 1H, CHCO), 0.78-1.82 (m, 10H, cyclohexyl protons).

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-(4-amino-2-methoxyphenyl)piperazine (Compound 70G)

A solution of compound 70F (0.030 g) and 98% hydrazine hydrate (0.06 mL) in EtOH (3 mL) was stirred at r.t. for 1.5 h. The solvent was evaporated to ⅓ of the initial volume and 1 N HCl (4 mL) was added. The suspension was filtered and the filtrate was basified with 1 N NaOH and extracted with EtOAc (2×10 mL). The combined organic phases were dried (Na₂SO₄) and the solvent was evaporated under vacuum to give 0.030 g (99%) of the title compound.

¹H-NMR (DMSO-d₆, δ): 8.10 (d, 1H, nitrophenyl ring H3), 7.72 (dd, 1H, nitrophenyl ring H5), 7.50-7.65 (m, 2H, nitrophenyl ring H4 and H6), 6.79 (d, 1H, methoxyphenyl ring H5 (H6)), 6.20-6.35 (m, 2H, methoxyphenyl ring H3 and H6 (H5)), 3.56-4.23 (m, 5H, CONCH ₂CH₂N and CH₃O), 2.30-3.32 (m, 12H, piperazine protons, NH₂ and CONCH₂CH ₂N), 1.85-2.05 (m, 1H, CHCO), 0.75-1.78 (m, 10H, cyclohexyl protons).

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-(4-acetylamino-2-methoxyphenyl)piperazine

The title compound was prepared following the procedure of example 28 but using compound 70G instead of compound 27 and CHCl₃ instead of CH₂Cl₂. Usual work-up and evaporation of the solvent afforded the title compound. Yield: 99%.

¹H-NMR (CDCl₃, δ): 8.10 (d, 1H,nitrophenyl ring H3), 7.78 (dd, 1H, nitrophenyl ring H5), 7.48-7-70 (m, 4H, methoxyphenyl ring H5 (H6), NH and nitrophenyl ring H4 and H6), 6.69-6.87 (m, 2H, methoxyphenyl ring H3 and H6 (H5)), 3.96-4.40 (m, 2H, CONCH ₂CH₂N), 3.85 (s, 3H, CH₃O), 2.89-3.72 (m,10H, piperazine protons and CONCH₂CH ₂N), 2.18 (s, 3H, CH₃CO), 1.80-1.98 (m, 1H, CHCO), 0.72-1.78 (m, 10H, cyclohexyl protons).

EXAMPLE 71

1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-trifluoromethoxyphenyl)piperazine

The title compound was obtained following the procedure described for example 54, but using 1-(2-trifluoromethoxyphenyl)piperazine in place of 1-(4-nitro-2-methoxyphenyl)piperazine. The reaction mixture was heated at 120° C. for 8 h. The residue obtained by usual work-up and extraction with Et₂O was purified by flash chromatography (petroleum ether-EtOAc gradient from 90:10 to 80:20) to afford the title compound. Yield: 41%.

¹H-NMR (CDCl₃, δ): 7.09-7.30 (m, 4H1, trifluoromethoxyphenylamino ring CHs), 6.90-7.09 (m, 2H, trifluoromethoxyphenyl ring CHs), 6.58-6.80 (m, 2H, trifluoromethoxyphenyl ring CHs), 4.92 (s, 1H, NH); 2.98-3.38 (m, 6H, HNCH ₂CH₂, piperazine protons), 2.45-2.85 (m, 6H, HNCH ₂CH₂, piperazine protons).

EXAMPLE 72

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-trifluoromethoxyphenyl)piperazine

The title compound was synthesized following the procedure of example 55, but using the compound of example 71 instead of the compound of example 54. The residue was purified by flash chromatography (petroleum ether-EtOAc 80:20). Yield: 56%.

¹H-NMR (CDCl₃, δ): 7.28-7.48 (m, 4H, trifluoromethoxyphenylamino ring CHs), 7.10-7.25 (m, 2H, 2-trifluoromethoxyphenyl ring CHs), 6.90-7.05 (m, 2H, 2-trifluoromethoxyphenyl ring CHs), 4.20-4.40 (m, 1H, CONCH(H)CH₂), 3.20-3.40 (m, 1H, CONCH(H)CH₂), 2.95-3.15 (m, 4H, piperazine protons), 2.45-2.75 (m, 6H, CONCH(H)CH ₂, piperazine protons), 1.85-2.05 (m, 1H, CHCO), 0.80-1.80 (m, 10H, cyclohexyl protons).

EXAMPLE 73

1-[N-(2-nitrophenyl)-N-(5-thiazolylcarbonyl)-2-aminoethyl)]-4-(2-methoxyphenyl)piperazine

The title compound was prepared following the procedure described for the compound in example 32, except that 5-thiazolecarbonyl chloride (prepared as described in EP0296673) was used in place of 3-furylcarbonyl chloride. The crude was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 100:1). Yield: 68%.

¹H-NMR (DMSO-d₆, δ): 9.06 (s, 1H, thiazole H2), 8.17 (dd, 1H, nitrophenyl ring H3), 7.81-7.96 (m, 2H, nitrophenyl ring H4 and H6), 7.62-7.81 (m, 1H, nitrophenyl ring H5), 7.45 (s, 1H, thiazole H4), 6.70-6.98 (m, 4H, methoxyphenyl ring CHs), 3.80-4.10 (m, 2H, CONCH ₂CH₂), 3.71 (s, 3H, CH₃O), 2.45-2.90 (m, 6H, CONCH₂CH ₂, piperazine protons), 2.20-2.40 (m, 4H, piperazine protons).

EXAMPLE 74

1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-bromo-5-methoxybenzyl)piperazine

The title compound was prepared following the method described for the compound of example 50 but substituting 1-(2-bromo-5-methoxybenzyl)piperazine (prepared as described in CAN 2,188,484) for 1-(4-indolyl)piperazine and heating at 120° C. for 5 h. The residue was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 100:1) to afford the title compound. Yield: 32%.

¹H-NMR (CDCl₃, δ): 7.43 (d, 1H, benzyl H3), 7.05-7.23 (m, 3H, benzyl H6 and trifluoromethoxyphenyl ring H3 and H5), 6.59-6.78 (m, 3H, benzyl H4 and trifluoromethoxyphenyl ring H4 and H6), 4.90 (bs, 1NH), 3.82 (s, 3H, CH₃O), 3.56 (s, 2H, benzylic CH₂), 3.10-3.28 (m, 2H, HNCH ₂CH₂), 2.68 (t, 2H, HNCH₂CH ₂), 2.42-2.62 (m, 8H, piperazine protons).

EXAMPLE 75

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-bromo-5-methoxybenzyl)piperazine

The title compound was prepared following the procedure described for the compound of example 55, substituting the compound of example 74 for the compound of example 54. The residue was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 100:1). Yield: 67%.

¹H-NMR (CDCl_(3, δ):) 7.40-7.60 (m, 5H, trifluoromethoxyphenyl ring CHs, benzyl 3H), 7.07 (d, 1H, benzyl H6), 6.65 (dd, 1H, benzyl H4), 4.18-4.38 (m, 1H, CONCH(H)), 3.78 (s, 3H, CH₃O), 3.55 (s, 2H, benzylic CH₂), 3.15-3.35 (m, 1H, CONCH(H)), 2.32-2.70 (m, 10H, CONCH₂CH ₂, piperazine protons), 1.83-2.03 (m, 1H, CHCO), 0.75-1.75 (m, 10H, cyclohexyl protons).

EXAMPLE 76

1-[N-cyclohexylcarbonyl-N-(2-iodophenyl)-2-aminoethyl]-4-(4-indolyl)piperazine

Preparation of N-(2-iodophenyl)cyclohexanecarboxamide (Compound 76A)

This compound was prepared following the procedure described for compound 26A in example 26, except that 2-iodoaniline was used in place of 2-trifluoromethylaniline. Yield 84%.

¹H-NMR (CDCl₃, δ): 8.25 (dd, 1H, H3 (6)), 7.75 (dd, 1H, H6 (3)), 7.40-7.60 (bs, 1H, NH 7.30 (dt,1H,H5 (4)), 6.80 (dt, 1H, H4 (5)), 2.30 (tt, 1H, CHCO), 1.20-2.10 (m, 10H, cyclohexyl protons).

Preparation of 1-(2-chloroethyl)-4-(4-indolyl)piperazine (Compound 76B)

8.3 mL of 1-bromo-2-chloroethane, 1.2 g of 1-(4-indolyl)piperazine and 1.2 mL of DIPEA was stirred at 60° C. for 3 h under nitrogen atmosphere. To the solution, cooled at r.t., was added 30 mL of H₂O. The mixture was then extracted with CH₂Cl₂-MeOH 7:3 (3×15 mL). The organic layer, dried on an. Na₂SO₄, was evaporated to dryness. The crude was purified by flash chromatography (CH₂Cl₂-MeOH 98:2) to give 0.57 g (36%) of the title compound.

¹H-NMR (CDCl₃, δ): 11.05 (s, 1H, NH), 6.90-7.35 (m, 3H, H2, H6, H7), 6.45 (d, 1H, H5), 6.35 (t, 1H, H3), 3.70 (t, 2H, CH₂CH ₂Cl), 3.00-3.15 (m, 4H, piperazine protons), 2.55-2.80 (m, 6H, CH ₂CH₂Cl, piperazine protons).

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-iodophenyl)-2-aminoethyl]-4-(4-indolyl)piperazine

The title compound was prepared following the procedure described for compound of example 39 but using compound 76A instead of compound 39A and compound 79B instead of 1(2-chloroethyl)-4-(2-methoxyphenyl)piperazine. The residue was purified by flash chromatography (CH₂Cl₂-MeOH 98:2). Yield: 19%.

¹H-NMR (CDCl₃, δ): 8.10-8.30 (br, 1H, NH), 7.95 (dd, 1H, phenyl ring H3), 7.35-7.50 (m, 2H, phenyl ring H5, H4), 7.00-7.20 (m, 4H, phenyl ring H6, indolyl H2, H6, H7), 6.50-6.65 (m, 2H, indolyl H5, H3), 4.40-4.60 (m, 1H, CONCH(H)CH₂),3.05-3.35 (m, 5H, CONCH(H)CH₂, piperazine protons), 2.55-2.85 (m, 6H, CONCH₂CH ₂, piperazine protons), 0.70-1.90 (m, 11H, cyclohexyl protons).

EXAMPLE 77

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-trifluoromethoxyphenyl)piperazine

Preparation of 1-(2-hydroxyethyl)-4-(2-trifluoromethoxyphenyl)piperazine (Compound 77A)

A stirred mixture of 1.23 g of 1-(2-trifluoromethoxyphenyl)piperazine, 0.73 mL of 97% 2-bromoethanol, 1.25 mL of DIPEA and 4 mL of DMF was heated at 65° C. for 6 h. After cooling to r.t., the mixture was diluted with H₂O (50 mL) and extracted with CH₂Cl₂ (3×30 mL). The organic layer was dried (anhydrous Na₂SO₄) and evaporated to dryness in vacuo. The residue was purified by flash chromatography (CH₂Cl₂-MeOH 100:1.5) affording 0.911 g (63%) of the title compound.

¹H-NMR (CDCl₃, δ): 7.15-7.26 (m, 2H, phenyl ring protons), 6.90-7.08 (m, 2H, phenyl ring protons), 3.65 (t, 2H, CH ₂OH), 3.02-3.18 (m, 4H, piperazine protons), 2.55-2.75 (m, 6H, piperazine protons, CH ₂CH₂OH). The OH signal is not detectable.

Preparation of 1-(2-chloroethyl)-4-(2-trifluoromethoxyphenyl)piperazine (Compound 77B)

The title compound was prepared following the procedure described for compound 50B of example 50 but substituting compound 77A for compound 50A. The residue was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 100:1). Yield: 86%.

¹H-NMR (CDCl₃, δ): 7.02-7.15 (m, 2H, phenyl ring protons), 6.90-7.00 (m, 2H, phenyl ring protons), 3.65 (t, 2H, CH₂Cl), 3.04-3.20 (m, 4H, piperazine protons), 2.80 (t, 2H, CH ₂CH₂Cl), 2.40-2.75 (m, 4H, piperazine protons).

Preparation of 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-trifluoromethoxyphenyl)piperazine

The title compound was prepared following the procedure described for compound of example 39 but using compound 43A instead of compound 39A and compound 77B instead of 1-(2-chloroethyl)-4-(2-methoxyphenyl)piperazine. The mixture was refluxed for 6 h. The residue was purified by flash chromatography (petroleum ether-EtOAc 70:30). Yield: 38%.

¹H-NMR (CDCl₃, δ): 7.60-7.80 (m, 2H, cyanophenyl ring CHs), 7.48-7.55 (m, 2H, cyanophenyl ring CHs), 7.10-7.25 (m, 2H, trifluoromethoxyphenyl ring CHs), 6.90-7.05 (m, 2H, trifluoromethoxyphenyl ring CHs), 4.05-4.25 (m, 1H, CONCH(H)CH_(2),) 3.60-3.85 (m, 1H, CONCH(H)CH₂), 2.85-3.12 (m, 4H, piperazine protons), 2.45-2.75 (m, 6H, CONCH₂CH ₂, piperazine protons), 0.70-2.10 (m, 11H, cyclohexyl protons).

EXAMPLE 78

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine

Preparation of 1-(2-hydroxyethyl)-4-(2-methoxy-4-nitrophenyl)piperazine (Compound 78A)

The title compound was synthesised following the procedure described for compound 77A of example 77 using 1-(2-methoxy-4-nitrophenyl)piperazine instead of 1-(2-trifluoromethoxyphenyl)piperazine. The residue was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 100:3) to afford the title compound Yield: 52%.

¹H-NMR (CDCl₃, δ): 7.85 (dd, 1H, H5), 7.70 (d, 1H, H3), 6.90 (d, 1H, H6), 3.95 (s, 3H, CH₃O), 3.66 (t, 2H, CH ₂OH), 3.20-3.35 (m, 4H, piperazine protons), 2.50-2.90 (br, 1H, OH), 2.68-2.80 (m, 4H, piperazine protons), 2.62 (t, 2H, CH ₂CH₂OH).

Preparation of 1-(2-chloroethyl)-4-(2-methoxy-4-nitrophenyl)piperazine (Compound 78B)

The title compound was prepared following the procedure described for compound 50B of example 50 but substituting compound 78A for compound 50A. the residue was purified by flash chromatography (petroleum ether-EtOAc 1:1). Yield: 94%.

¹H-NMR (CDCl₃, δ): 7.86 (δδ, 1H, H5), 7.71 (d, 1H, H3), 6.87 (d, 1H, H6), 3.95 (s, 3H, CH₃O), 3.65 (t, 2H, CH₂Cl), 3.20-3.32 (m, 4H, piperazine protons), 2.82 (t, 2H, CH ₂CH₂Cl), 2.65-2.75 (m, 4H, piperazine protons).

Preparation of 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methox-4-nitrophenyl)piperazine

The title compound was prepared following the procedure described for compound of example 39 but using compound 43A instead of compound 39A and compound 78B instead of 1-(2-chloroethyl)-4-(2-methoxyphenyl)piperazine.

The residue was purified by flash chromatography (petroleum ether-EtOAc gradient from 70:30 to 40:60). Yield: 32%.

¹H-NMR (CDCl₃, δ): 7.86 (dd, 1, methoxyphenyl ring H5), 7.60-7.80 (m, 3H, methoxyphenyl ring H3, cyanophenyl ring H3 and H6), 7.33-7.55 (m, 2H, cyanophenyl ring H4 and H5), 6.83 (d, 1H, methoxyphenyl ring H6), 3.98-4.22 (m, 1H, CONCH(H)), 3.90 (s, 3H, CH₃O), 3.63-3.85 (m, 1H, CONCH(H)), 2.95-3.28 (m, 4H, piperazine protons), 2.48-2.75 (m, 6H, piperazine protons, CONCH₂CH ₂), 0.70-2.10 (m, 11H, cyclohexyl protons).

EXAMPLE 79

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-amino-2-methoxyphenyl)piperazine

The title compound was synthesized as described for the compound of example 27 but using the compound of example 78 instead of the compound of example 2 and heating at reflux for 3 h. The residue was purified by flash chromatography (CH₂Cl₂-2 N methanolic NH₃ 100:2). Yield: 54%.

¹H-NMR (CDCl₃, δ): 7.61-7.82 (m, 2H, cyanophenyl ring CHs), 7.41-7.58 (m, 2H, cyanophenyl ring CHs), 6.66-6.83 (m, 1H, methoxyphenyl ring H6), 6.17-6.32 (m, 2H, methoxyphenyl ring H3 and H5), 4.05-4.30 (m, 1H, CONCH(H)), 3.66-3.92 (m, 1H, CONCH(H)), 3.80 (s, 3H,CH₃O), 3.30-3.68 (br, 2H, NH₂),2.30-3.20 (m, 10H, CONCH₂CH ₂, piperazine CH₂s), 0.75-2.15 (m, 11H, cyclohexyl protons).

EXAMPLE 80

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-acetylamino-2-methoxyphenyl)piperazine

The title compound was synthesized according to the procedure reported in example 28 but substituting the compound of example 79 for the compound of example 27 and stirring at 20-25° C. for 17 h. The usual work-up afforded the title compound. Yield: 49%.

¹H-NMR (CDCl₃, δ): 7.60-7.82 (m, 2H, cyanophenyl ring CHs), 7.40-7.60 (m, 2H, cyanophenyl ring CHs), 7.32 (bs, 1H, methoxyphenyl ring CH), 7.15 (s, 1H, NHCO), 7.80 (bs, 2H, methoxyphenyl ring CHs), 4.05-4.30 (m, 1H, CONCH(H)CH₂), 3.65-3.95 (m, 1H, CONCH(H)CH₂), 3.82 (s, 3H, OCH₃) 2.40-3.30 (m, 10H, CONCH₂CH ₂, piperazine CH₂s), 2.20 (s, 3H, COCH₃), 0.70-2.10 (m, 11H, cyclohexyl protons).

EXAMPLE 81

1-[N-(2-acetylphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

Preparation of N-(2-acetylphenyl)cyclohexanecarboxamide (Compound 81A)

This compound was prepared following the procedure described for compound 26A of example 26, except that 2-acetylaniline was used in place of 2-trifluoromethylaniline. Yield: 90%.

Preparation of N-[2-(2-methyl-1,3-dioxolan-2-yl)phenyl]cyclohexanecarboxami-de (Compound 81B)

A solution of 8 mL of ethylene glycol, 0.23 g of compound 81A and 0.03 g of p-toluenesulphonic acid.H₂O in 20 mL of toluene was refluxed for 6 h removing H₂O by a Dean-Stark apparatus. The solution was washed with H₂O (10 mL) and 5% NaHCO₃ (2×10 mL). The dried (Na₂SO₄) organic phase was evaporated to dryness and the residue was purified by flash chromatography (petroleum ether-EtOAc 95:5) to give 0.11 g (42%) of the title compound.

¹H-NMR (CDCl₃, δ): 9.25 (s, 1H, NH), 8.25 (dd, 1H, phenyl ring H6), 7.45 (dd, 1H, phenyl ring H3), 7.28 (t, 1H, phenyl ring H4), 7.05 (t, 1H, phenyl ring H5), 3.95-4.12 and 3.75-3.90 (2m, 4H, OCH₂CH₂O), 2.25 (tt, 1H, CHCO), 1.68 (s, 3H, CH₃), 1.20-2.10 (m, 10H, cyclohexyl protons).

Preparation of 1-[N-cyclohexanecarbonyl-N-[2-(2-methyl-1,3-dioxolan-2-yl)phenyl]-2-aminoethyl]-4-(2-methoxyphenyl)piperazine (Compound 81C).

The title compound was prepared following the procedure described for compound of example 39 but using compound 81B instead of compound 39A and reflux lasted 9 h. The residue was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 100:2) to give of the title compound. Yield: 40%.

¹H-NMR (CDCl₃, δ): 7.67-7.73 (m, 1H, phenyl ring H6), 7.25-7.35 (m, 3H, phenyl ring H3, H4, H5), 6.80-7.05 (m, 4H, methoxyphenyl ring protons), 4.40-4.63 (m, 1H CONCH(H)CH₂) 3.95-4.12 and 3.75-3.90 (2m, 4H, OCH₂CH₂O), 3.85 (s, 3H, OCH₃), 295-3.23 (m, 5H, CONCH(H)CH₂, piperazine protons), 2.55-2.90 (m, 6H, CONCH₂CH ₂, piperazine protons), 1.65 (s, 3H, CH₃), 0.75-1.90 (m, 11H, cyclohexyl protons),

Preparation of 1-[N-(2-acetylphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine

A solution of 0.10 g of compound 81C and 0.09 g of PTSA H₂O in 4 mL of Me₂CO was stirred at 20-25° C. for 15 h. Afterwards, the solution was poured into 10 mL of H₂O, alkalinized with 5% NaHCO₃ and extracted with CH₂Cl₂ (3×7 mL,). The dried (Na₂SO₄) organic layer was evaporated to dryness and purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 100:2) to give 0.05 g (54%) of the title compound.

¹H-NMR (CDCl₃, δ): 7.75 (dd, 1H, phenyl ring H6), 7.35-7.60 (m, 3H, phenyl ring H3, H4, H5), 6.80-7.05 (m, 4H, methoxyphenyl ring CHs), 4.27-4.45 (m, 1H, CONCH(H)CH₂),3.85 (s, 3H, OCH_(3),) 2.95-3.20 (m, 5H, CONCH(H)CH₂, piperazine protons), 2.47-2.85 (m, 6H, CONCH₂CH ₂, piperazine protons), 2.50 (s, 3H, CH₃), 1.80-2.05 (m, 1H, CHCO), 0.75-1.80 (m, 10H, cyclohexyl protons).

EXAMPLE 82

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-indolyl)piperazine

The title compound was prepared following the procedure described for compound of example 39 but using compound 43A instead of compound 39A and compound 76B instead of 1-(2-chloroethyl)-4-(2-methoxyphenyl)piperazine. The mixture was stirred at 100° C. for 4.5 h. The residue was purified by flash chromatography (toluene-Me₂CO 85:15). Yield: 22%.

¹H-NMR (CDCl₃, δ): 8.20-8.35 (br, 1H, NH), 7.75 and 7.65 (2dd, 2H, phenyl ring H3, H6), 7.40-7.57 (m, 2H, phenyl ring H4, H5), 7.00-7.25 (m, 3H, indolyl H2, H6, H7), 6.55 (dd, 1H, indolyl H5), 6.50 (t, 1H, indolyl H3), 4.10-4.30 (m, 1H, CONCH(H)CH₂), 3.70-3.95 (m, 1H, CONCH(H)CH₂), 3.05-3.35 (m, 4H, piperazine protons), 2.55-2.90 (m, 6H, piperazine protons, CONCH₂CH ₂), 1.95 (t, 1H, CHCO), 0.80-1.90 (m, 10H, cyclohexyl protons).

EXAMPLE 83

1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-bromo-5-methoxybenzyl)piperazine

Preparation of 1-(2-bromo-5-methoxybenzyl)-4-(2-hydroxyethyl)piperazine (Compound 83A)

The title compound was synthesised following the procedure described in example 77 for compound 77A using 1-(2-bromo-5-methoxybenzyl)piperazine instead of 1-(2-trifluoromethoxyphenyl)piperazine and heating at 65° C. for 6 h. The residue was purified by flash chromatography (CHCl₃-2 N methanolic NH₃ 100:3). Yield: 62%.

¹H-NMR (CDCl₃, δ): 7.42 (d, 1H3), 7.16 (d, 1H, H6), 6.68 (dd, 1H, H4), 3.80 (s,3H, CH₃O), 3.52-3.68 (m, 4H, CH ₂OH, benzylic CH₂), 2.40-2.80 (m, 11H, CH ₂CH₂OH, piperazine protons).

Preparation of 1-(2-bromo-5-methoxybenzyl)-4-(2-chloroethyl)piperazine (Compound 83B)

The title compound was prepared following the procedure described for compound 50B of example 50but substituting compound 83A for compound 50A. The residue was purified by flash chromatography (petroleum ether-EtOAc 1:1). Yield: 15%.

¹H-NMR (CDCl₃, δ): 7.42 (d, 1H, H3), 7.08 (d, 1, H6), 6.68 (dd, 1H, H4), 3.80 (s, 3H, CH₃O), 3.51-3.65 (m, 4H, benzylic CH₂, CH₂CH ₂Cl), 2.75 (t, 2H, CH ₂CH₂Cl) 2.60 (s, 8H, piperazine protons).

Preparation of 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-bromo-5-methoxybenzyl)piperazine

The title compound was prepared following the procedure described for compound of example 39 but using compound 43A instead of compound 39A and compound 83B instead of 1-(2-chloroethyl)-4-(2-methoxyphenyl)piperazine. Reflux was maintained for 7 h. The residue was purified by flash chromatography (petroleum ether-EtOAc gradient from 1:1 to 20:80). Yield: 38%.

¹H-NMR (CDCl₃, δ): 7.55-7.82 (m, 2H, cyanophenyl ring H3 and H6), 7.30-7.55 (m, 3H, cyanophenyl ring H4 and H5, benzyl ring H3), 6.90-7.20 (m, 1H, benzyl ring H6), 6.68 (dd, 1H, benzyl ring H4), 3.92-4.25 (m, 1H, CONCH(H)CH₂), 3.70-3.92 (m, 1H, CONCH(H)CH₂), 3.80 (s, 3H, OCH₃), 3.30-3.70 (m, 2H, benzylic CH₂) 2.10-3.10 (m, 10H,CONCH₂CH ₂, piperazine protons), 0.70-2.05 (m, 11H, cyclohexyl protons).

EXAMPLE 84

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(1-cyclohexylcarbonyl-4-indolyl)piperazine

The title compound was obtained as a by-product during the synthesis of the compound of example 51. Yield: 10%.

¹H-NMR (CDCl₃, δ): 8.15 (dd, 1H,indolyl H7), 7.18-7.55 (m, 6H, indolyl H2 and H6, trifluoromethoxyphenyl ring CHs), 6.75 (dd, 1H, indolyl H5), 6.65 (dd, 1H, indolyl H3), 4.12-4.25 (m, 1H,CONCH(H)CH₂), 2.95-3.50 (m, 6H, CONCH(H)CH₂, CHCO, piperazine protons), 2.40-2.85 (m, 6H, CONCH₂CH ₂, piperazine protons), 0.70-2.10 (m, 21H, CHCO, cyclohexyl protons).

EXAMPLE 85

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(8-quinolyl)piperazine

Preparation of N-(2-trifluoromethoxyphenyl)cyclohexanecarboxamide (Compound 85A)

This compound was prepared following the procedure described for compound 26A of example 26, except that 2-trifluoromethoxyaniline was used in place of 2-trifluoromethylaniline. Yield: 100%.

¹H-NMR (CDCl₃, δ): 8.44 (dd, 1H, phenyl ring H6), 7.47 (bs, 1H, CONH),7.21-7.30 (m, 2H, phenyl ring H4, H5), 7.08-7.14 (m, 1H, phenyl ring H3), 2.21-2.43 (m, 1H, CHCO), 1.20-2.08 (m, 10H, cyclohexyl protons).

Preparation of N-(2,2-dimethoxyethyl)-N-(2-trifluoromethoxy phenyl)cyclohexanecarboxamide (85B)

A solution of compound 85A (0.15 g) in toluene (20 mL) was heated to reflux and 5 mL of toluene distilled off; then t-BuOK (0.09 g) was added and the mixture heated to reflux removing by evaporation 2 ml of the solvent; then 2-bromoacetaldehyde dimethyl acetal (0.09 mL) was dropped. The resulting suspension was refluxed under N₂ atmosphere for 12-15 h. After cooling to room temperature, the solvent was evaporated to dryness in vacuo and the crude purified by flash chromatography (petroleum ether-EtOAc 9:1), affording 0.106 g (54%) of the title compound as an oil.

¹H-NMR(CDCl₃, δ): 7.31-7.48 (m, 4H, phenyl ring CHs), 4.61-4.70 (m, 1H, CH(OCH₃)₂), 4.16-4.24 (m, 1H, CONCH(H)), 3.39 (s, 3H, OCH₃) 3.32 (s, 3H, OCH₃),3.13-3.24 (m, 1H, CONCH(H)), 1.92-2.09 (m, 1H, CHCO), 0.85-1.79 (m, 10H, cyclohexyl protons).

Preparation of N-(2-oxoethyl)-N-(2-trifluoromethoxyphenyl)cyclohexanecarboxamide (85C)

A suspension of compound 85B (0.106 g), hydroquinone (0.003 g) in 2 N HCl (1.14 mL) was heated at 80° C. for 30-40 minutes. After cooling to room temperature, NaHCO₃ was added (pH=7) and the resulting mixture was extracted with CH₂Cl₂ (3×10 mL).The combined organic layers were dried (Na₂SO₄), filtered and evaporated to dryness at reduced pressure to give 0.081 g (88%) of the title compound as an oil.

¹H-NMR (CDCl₃, δ): 9.62 (s, 1H,CHO), 7.29-7.57 (m, 4H, phenyl ring CHs), 4.67 (d, 1H, NCH(H)CHO), 3.86 (d, 1H, NCH(H)CHO), 2.02-1.98 (m, 1H, CHCO), 0.85-1.83 (m, 10H, cyclohexyl protons).

Preparation of 1-(8-quinolyl)piperazine (85D)

A mixture of 8-aminoquinoline (1.5 g), bis-(2-chloroethyl)amine hydrochloride (2.04 g), o-dichlorobenzene (4.5 mL) and n-hexanol (0.45 mL) was stirred at reflux temperature for 5 h. After cooling to room temperature, the mixture was treated with 2 N NaOH (10 mL) and extracted with CH₂Cl₂ (3×20 mL). The purification was carried out by flash chromatography (CH₂Cl₂-2 N methanolic NH₃) 97:3 to give 0.48 g (22%) of the title compound.

¹H-NMR (CDCl₃, δ): 8.80 (dd, 1H, quinolyl H2), 8.17 (dd, 1H, quinolyl H4), 7.32-7.53 (m, 3H, quinolyl H6, H5, H3), 7.12 (m, 1H , quinolyl H7), 3.38-3.51 (m, 4H, piperazine protons), 3.21-3.32 (m, 4H, piperazine protons), 2.21 (bs, 1H, NH).

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(8-quinolyl)piperazin

To a solution of compound 85 C. (0.081 g), compound 85D (0.06 g) and acetic acid (0.06 mL) in 1,2-DCE (10 mL) stirred under N₂ atmosphere, NaB(Oac)₃H (0.078 g) was added. The resulting mixture was stirred for 2 h at 20-25° C., alkalinized with 1 N NaOH (pH=8) and extracted with CH₂Cl₂ (3×10 mL). The organic layer was dried over Na₂SO₄, filtered and evaporated at reduced pressure. The crude was purified by flash chromatography (toluene-acetone 75:25) to give 0.09 g (73%) of the title compound. M.p. 141.5-143° C.

¹H-NMR (CDCl₃, δ): 8.86 (dd, 1H, quinolyl H2), 8.14 (dd, 1H, quinolyl H4), 7.30-7.52 (m, 7H, quinolyl H3, H5, H6 and phenyl ring CHs), 7.09-7.18 (m, 1H, quinolyl H7), 4.32-4.47 (m, 1H, CONCH(H)CH₂N), 3.21-3.51 (m, 5H, piperazine protons and CONCH(H)CH₂N), 2.53-2.94 (m, 6H, piperazine protons and CONCH₂CH ₂N), 1.89-2.07 (m, 1H, CHCO), 0.81-1.79 (m, 10H, cyclohexyl protons).

EXAMPLE 86

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-amino-2-cyanophenyl)piperazine

Preparation of 1-(2-cyano-4-nitrophenyl)piperazine (Compound 86A)

A mixture of 2-chloro-5-nitrobenzonitrile (1 g) and piperazine (2.12 g) in ethylene glycol monomethyl ether (5 mL) was heated at 60° C. for 30 minutes. After cooling to room temperature, H₂O was added (50 mL) and the solution extracted with CH₂Cl₂ (3×25 mL). The combined organic layers were washed with H₂O, dried over Na₂SO₄ and evaporated to dryness to give 1.27 g (99%) of the desired compound.

¹H-NMR (CDCl₃, δ): 8.46 (d, 1H , phenyl H3), 8.27 (dd, 1H, phenyl H5), 6.68 (d, 1H, phenyl H6), 3.48-3.56 (m, 4H, piperazine protons), 3.03-3.14 (m, 4H, piperazine protons), 1.75 (bs, 1H, NH).

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-cyano-4-nitrophenyl)piperazine (Compound 86B)

The title compound was prepared following the method described in example 85 substituting compound 86A for 1-(8-quinolyl)piperazine.

The crude was purified by flash chromatography (toluene-acetone 9:1). Yield: 76%.

1H-NMR (CDCl₃, δ): 8.53 (δδ, 1H, cyanophenyl ring H3), 8.27 (dd, 1H, cyanophenyl ring H5), 7.29-7.49 (m, 4H, trifluoromethoxyphenyl ring CHs), 6.96 (d, 1H, cyanophenyl ring H6), 4.22-4.41 (m 1H, CONCH(H)CH₂N), 3.41-3.60 (m, 4H, piperazine protons), 3.21-3.39 (m, 1H, CONCH(H)CH₂N), 2.70-2.83 (m, 2H, CONCH₂CH ₂N), 2.47-2.69 (m, 4H, piperazine protons), 1.88-2.07 (m, 1H, CHCO), 0.83-1.79 (m, 10H, cyclohexyl protons).

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-amino-2-cyanophenyl)piperazine

The title compound was prepared as described in example 27 using the compound 86A of example 86 instead of the compound of example 1. The crude was purified twice by flash chromatography (EtOAc-MeOH 95:5, then toluene-acetone 75:25). Yield: 43%.

¹H-NMR (CDCl₃, δ): 7.48-7.69 (m, 4H, trifluoromethoxyphenyl ring CHs), 6.86-6.98 (m, 1H, cyanophenyl ring H6), 6.76-6.84 (m, 2H, cyanophenyl ring H3, H5), 5.17 (s, 2H, NH₂), 4.01-4.20 (m, 1H, CONCH(H)CH₂N), 3.09-3.28 (m, 1H, CONCH(H)CH₂N), 2.72-2.93 (m, 4H, piperazine protons), 2.31-2.59 (m, 6H, CONCH₂CH ₂N and piperazine protons), 1.76-1.97 (m, 1H, CHCO), 0.72-1.73 (m, 10H, cyclohexyl protons).

EXAMPLE 87

1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-cyanophenyl)piperazine

The title compound was prepared following the method described in example 85 substituting 1-(2-cyanophenyl)piperazine for 1-(8-quinolyl)piperazine. The crude was purified by flash chromatography (toluene-Me₂CO 8:2). Yield: 26%.

¹H-NMR (CDCl₃, δ): 7.25-7.60 (m, 6H, phenyl ring CHs), 6.90-7.10 (m, 2H, phenyl ring ring CHs), 4.40 (dd, 1H , CONCH(H)CH₂N), 3.00-3.45 (m, 5H, piperazine protons and CONCH(H)CH₂N), 2.40-2.90 (m, 6H, CONCH₂CH ₂N and piperazine protons), 1.80-2.03 (m, 1H, CHCO), 0.72-1.75 (m, 10H, cyclohexyl protons).

EXAMPLE 88

1-[N-cyclohexylcarbonyl-N-(2-methanesulphonylaminophenyl)-2-aminoethyl]-4-(4-indolyl)piperazine

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-aminophenyl)-2-aminoethyl]-4-(4-indolyl)piperazine (Compound 88A)

The title compound was prepared following the procedure described in example 27 using the compound of example 13 instead of the compound of example 2. The residue, purified by flash chromatography (CH₂Cl₂-2N methanolic NH₃ 98:2). Yield: 61%.

¹H-NMR (CDCl₃, (δ): 8.10-8.35 (br, 1H, indolyl NH), 7.00-7.20 (m, 4H, indolyl H2, H6, H7 and phenyl ring H4), 6.90 (dd, 1H, phenyl ring H6), 6.65-6.80 (m, 2H, phenyl ring H3, H5), 6.55 (dd, 1H, indolyl H5), 6.50 (t, 1H, indolyl H3), 4.00-4.80 (m, 2H, CONCH ₂CH₂), 2.30-3.40 (m, 12H, piperazine protons, NH₂, CONCH₂CH ₂), 2.10 (tt, 1H, CHCO), 0.80-2.00 (m, 10H, cyclohexyl protons).

Preparation of 1-[N-cyclohexylcarbonyl-N-(2-methanesulphonylaminophenyl)-2-aminoethyl]-4-(4-indolyl)piperazine

The title compound was prepared following the method described for compound of example 46 but using compound 88A instead of compound of example 27. The residue was purified by flash chromatography (CH₂Cl₂-2 N methanolic NH₃ 95:5). Yield: 24%.

¹H-NMR (CDCl₃, δ): 8.25 (br, 1H, indolyl NH), 7.55 (dd, 1H, phenyl ring CH), 7.30-7.45 (m, 1H, phenyl ring CH), 7.00-7.23 (m, 5H, phenyl ring CHs, indolyl H2, H6, H7), 6.65 (dd, 1H, indolyl H3), 6.50 (br, 1H, indolyl H5), 4.90-5.10 (m, 1H, CONCH(H)CH₂), 3.25-3.55 (m, 4H, piperazine protons), 3.15 (s, 3H, SO₂CH₃), 2.40-3.20 (m, 8H, piperazine protons, CONCH(H)CH ₂, CH₃SO₂NH), 0.70-2.10 (m, 11H, cyclohexyl protons).

EXAMPLE 89

1-[N-cyclohexylcarbonyl-N-(2-methoxyphenyl)-2-aminoethyl]-4-(1-cyclohexylcarbonyl-4-indolyl)piperazine

The title compound was obtained as by-product in the synthesis of the compound of example 48. The mother liquors of the hydrochloride crystallization were evaporated to dryness in vacuo and purified by flash chromatography (petroleum ether-EtOAc 60:40). Yield: 3%.

¹H-NMR (CDCl₃, δ): 8.15 (d, 1H, indolyl H7), 7.15-7.50 (m, 4H, trifluoromethoxyphenyl ring CHs), 6.90-7.15 (m, 2H, indolyl H2 and H6), 6.75 (dd, 1H, indolyl H5), 6.65 (dd, 1H, indolyl H3), 4.00-4.32 (m, 1H, CONCH(H)CH₂), 2.82 (s, 3H, CH₃O), 2.40-3.60 (m, 11H, CONCH(H)CH ₂, piperazine protons), 0.70-2.10 (m, 22H, cyclohexyl protons).

EXAMPLE 90

Effects on Volume-Induced Rhythmic Bladder Voiding Contractions in Anaesthetized Rats

A. Method

Female Sprague Dawley rats weighing 225-275 g (Crl: CDo BR, Charles River Italia) were used. The animals were housed with free access to food and water and were maintained on a forced 12 h alternating light-dark cycle at 22-24° C. for at least one week, except during the experiment. The activity on the rhythmic bladder voiding contractions was evaluated according to the method of Dray (J. Pharmacol. Methods, 13:157, 1985), with some modifications as in Guarneri (Pharmacol. Res., 27:173, 1993). Briefly, rats were anesthetized by subcutaneous injection of 1.25 g/kg (5 ml/kg) urethane, after which the urinary bladder was catheterized via the urethra using PE 50 polyethylene tubing filled with physiological saline. The catheter was tied in place with a ligature around the external urethral orifice and was connected with conventional pressure transducers (Statham P23 ID/P23 XL). The intravesical pressure was displayed continuously on a chart recorder (Battaglia Rangoni KV 135 with DCl/TI amplifier). The bladder was then filled via the recording catheter by incremental volumes of warm (37° C.) saline until reflex bladder voiding contractions occurred (usually 0.8-1.5 ml). For intravenous (i.v.) injection of bioactive compounds, PE 50 polyethylene tubing filled with physiological saline was inserted into the jugular vein. From the cystometrogram, the number of contractions recorded 15 min before (basal values) and after treatment, as well as the mean amplitude of these contractions (mean height of the peaks in mmHg) was evaluated.

Since most compounds produced an effect that was relatively rapid in onset and led to a complete cessation of bladder contractions, bioactivity was conveniently estimated by measuring the duration of bladder quiescence (i.e., the duration of time during which no contractions occurred). The number of animals tested showing a reduction in the number of contractions >30% of that observed in the basal period was also recorded.

To compare the potency of the tested compounds for inhibiting bladder voiding contractions, equieffective doses which resulted in a contraction disappearance time of 10 minutes (ED_(10 min)) were computed by means of least square linear regression analysis. Also computed in this manner were extrapolated doses which induced a reduction of the number of contractions of greater than 30% in 50% of treated rats (ED₅₀, frequency) by the method of Bliss (Bliss C. I., Quart. J. Pharm. Pharmacol. 11, 192-216, 1938). After the suppressive effects of drug injection wore off, the height of the contractile peaks was compared with the height of the peaks previously recorded after the control intravenous administration of vehicle. The potency of the tested compounds (ED₅₀ value: the extrapolated doses inducing a 30% reduction of amplitude of the contractions in 50% of treated rats) was evaluated on a quantal basis by the method of Bliss (Bliss C. I., Quart. J. Pharm. Pharmacol. 11, 192-216, 1938).

B. Results

The rapid distension of the urinary bladder in urethane-anesthetized rats produced a series of rhythmic bladder voiding contractions whose characteristics have been described and are well-known in the art (Maggi et al., Brain Res., 380:83, 1986, Maggi, et al., J. Pharmacol. Exp. Ther., 230:500, 1984). The frequency of these contractions is related to the sensory afferent arm of reflex micturition and to the integrity of the micturition center, while their amplitude is a property of the efferent arm of the reflex. In this model system, compounds that act mainly on the CNS (such as morphine) cause a block in voiding contraction, whereas drugs that act at the level of the detrusor muscle, such as oxybutynin, lower the amplitude of the bladder contractions. The results obtained after administration of prior art compounds and compounds of the invention are shown in Table 1.

Compound A, a prior art compound, was more potent than flavoxate and oxybutynin in inhibiting voiding contractions. This compound, in contrast to oxybutynin, did not affect the amplitude of the contraction, indicating no impairment of bladder contractility.

Surprisingly, however, compounds with substituents at position 2 of the aniline ring in Formula I, such as NO₂, such as the compound of Example 2, have significantly higher potency than unsubstituted compound A, particular with regard to the ED_(10 min) values. Like compound A, the compound of Example 2 does not affect bladder contractility. When compounds were synthesized with a nitro group at position 3 or 4 of the aniline ring, such as comparative compounds B and C, pharmacological activity was abolished.

Results similar (i.e., higher potency for the 2-substituted derivatives) to those obtained by Example 2 were obtained relative to compounds where R is H and which are unsubstituted or substituted at the 3- and 4-positions of the aniline ring. These results are shown in Table 1, where it can be seen that compounds AA, D, E, which are unsubstituted and 3- and 4-substituted compounds, are clearly inferior to the compounds of Examples 1, 10 and 11 and 18, i.e., 2-NO₂, 2-CN, 2-COCH₃ and 2-COOCH₃ derivatives. The compounds of the invention were clearly superior, particularly with regard to the ED₅₀ values which are indicators of urinary frequency.

TABLE 1 Effects on rhythmic bladder voiding contractions after intravenous administration. Data represent the ED_(10 min) values (the extrapolated dose inducing 10 min of disappearance of the contractions); the ED₅₀ values (the extrapolated doses inducing a reduction of the number of contractions >30% in 50% of treated rats) (frequency), and the ED₅₀ values (the extrapolated doses inducing 30% reduction of amplitude of the contractions in 50% of treated rats) (amplitude). ED50 ED50 Compound ED_(10 min) μg/kg (frequency) μg/kg (amplitude) μg/kg Compound A 650 33 n.a. Compound B >1000 >1000 n.a. Compound C >1000 >1000 n.a. Compound D >1000 >1000 n.a. Compound E >1000 >1000 n.a. Compound AA 663 244 n.a. Example 1 192 55 n.a. Example 2 60 9 n.a. Example 10 122 28 n.a. Example 11 318 40 n.a. Example 13 266 29 n.a. Example 18 101 17 n.a. Example 20 97 25 n.a. Example 23 93 18 n.a. Example 27 131 13 n.a. Example 42 33 18 n.a. Example 43 52 4 n.a. Example 47 181 20 n.a. Example 48 40 14 n.a. Example 51 276 200 n.a. Example 56 61 21 n.a. Example 57 254 252 n.a. Example 66 167 58 n.a. Example 69 60 14 n.a. Flavoxate >10000 2648 n.a. Oxybutinin 7770 >10000 240 n.a. = not active; no significant reduction of the height of peaks. Compound AA = 1-(N-phenyl-2-aminoethyl)-4-(2-methoxyphenyl)piperazine. Compounds A, B, C, D, E, see text.

EXAMPLE 91

Effects on Cystometric Parameters in Conscious Rats

A. Methods

Male Sprague Dawley rats (Crl: CDo BR) weighing 250-350 g were used. The animals were housed with free access to food and water and maintained on a forced 12 h alternating light-dark cycle at 22-24° C. for at least one week, except during performance of the experiment. To quantify urodynamic parameters in conscious rats, cystometrographic studies were performed using procedures previously described (Guarneri et al., Pharmacol. Res., 24:175, 1991). Male rats were anesthetized with nembutal (30 mg/kg) and chloral hydrate (125 mg/kg) i.p. and were placed in a supine position. An approximately 10 mm long midline incision was made in the shaved and cleaned abdominal wall. The urinary bladder was gently freed from adhering tissues, emptied, and then cannulated, via an incision at the dome, with a polyethylene cannula (Portex PP30), which was permanently sutured with silk thread. The cannula was exteriorized through a subcutaneous tunnel in the retroscapular area, where it was connected with a plastic adapter to avoid the risk of removal by the animal. For intravenous (i.v.) injection of test compounds, a PE 50 polyethylene tubing filled with physiological saline was inserted into the jugular vein and exteriorized in the retroscapular area. The rats were utilized exclusively one day after implantation. On the day of the experiment, the rats were placed in Bollman's cages, after a stabilization period of 20 min, and the free tip of the bladder catheter was connected through a T-shaped tube to a pressure transducer (Bentley T 800/Marb P 82) and to a peristaltic pump (Gilson minipuls 2) for a continuous infusion, at the constant rate of 0.1 ml/min, of saline solution into the urinary bladder. The intraluminal pressure signal during infusion was continuously recorded on a polygraph (Battaglia Rangoni KO 380 with ADCl/T amplifier).

Two urodynamic parameters were evaluated: bladder volume capacity (BVC) and micturition pressure (MP). BVC (in ml) is defined as the minimum volume infused after which detrusor contraction (followed by micturition) occurs. MP (in mm Hg) is defined as the maximal intravesical pressure induced by the contraction of detrusor during micturition. Basal BVC and MP values were calculated as the means of the first two recorded cystometrograms. At this point in the assay, the infusion was interrupted and the test compounds were administered. Fifteen minutes after intravenous administration two additional cystometrograms were recorded in each animal and the mean values of the two cystometrographic parameters were calculated. The statistical significance of the differences in urodynamic parameter values was evaluated by Student's t test for paired data.

B. Results

The effects of different doses of the tested compounds are shown in Table 2. Compound A behaved similarly to flavoxate by increasing BVC. Neither compound impaired bladder contractility, since no consistent changes in MP were observed. In contrast, oxybutynin markedly and dose-dependently decreased MP without effects on BVC. The compound of Example 2 was more potent than compound A and flavoxate; a significant increase in BVC was observed after the i.v. administration of 0.3 mg/kg of the compound of Example 2, compared with the requirement for administration of 1.0 mg/kg of flavoxate or compound A. The compound of Example 2 induced a slight, albeit significant, decrease in MP. This effect, however, was not dose-dependent and was markedly lower than that induced by oxybutynin.

TABLE 2 Effects on cystometrogram in conscious rats. Data represent mean values ± S.E. of bladder volume capacity (BVC; ml) and of micturition pressure (MP; mmHg), before and 15 min after i.v. injection of the compounds. Dose % COMPOUND μg/kg before after treatment of change BVC Compound A  300 0.81 ± 0.05 0.87 ± 0.05  +7.4 1000 0.78 ± 0.11 0.97 ± 0.11** +24.4 Example 2  300 0.71 ± 0.09 0.87 ± 0.10*  +22.5 1000 0.62 ± 0.09 0.75 ± 0.10** +21.0 Example 8  300 0.59 ± 0.04 0.71 ± 0.05*  +21.0 1000 0.65 ± 0.10 0.88 ± 0.12** +35.0 Example 13  100 0.94 ± 0.12 1.07 ± 0.14  +13.4  300 0.73 ± 0.09 0.95 ± 0.12** +30.2 Example 18  100 0.60 ± 0.07 0.80 ± 0.09*  +33.3 1000 0.63 ± 0.11 0.89 ± 0.16** +40.3 Example 23  300 0.50 ± 0.06 0.77 ± 0.03** +54.3 1000 0.66 ± 0.09 0.89 ± 0.12** +34.5 Example 42  300 0.70 ± 0.11 0.89 ± 0.15  +26.4 1000 0.70 ± 0.09 1.00 ± 0.16*  +41.7 Example 51  300 0.66 ± 0.11 0.84 ± 0.14** +27.7 1000 0.79 ± 0.05 1.08 ± 0.09** +36.5 FLAVOXATE  300 0.76 ± 0.11 0.87 ± 0.11  +14.5 1000 0.88 ± 0.15 1.11 ± 0.16** +26.1 OXYBUTYNIN  100 0.82 ± 0.15 0.89 ± 0.18  +8.5  300 0.83 ± 0.13 0.83 ± 0.12  ±0.0 1000 0.94 ± 0.19 1.00 ± 0.18  ±6.4 MP Compound A  300 90.6 ± 10.4 85.6 ± 11.3  −5.5 1000 90.2 ± 6.5  84.1 ± 5.2   −6.8 Example 2  300 95.4 ± 6.4  80.4 ± 6.5**  −15.7 1000 109.0 ± 12.1  99.6 ± 11.2*  −8.6 Example 8  300 116.1 ± 17.4  98.3 ± 17.2** −15.0 1000 81.3 ± 9.0  64.8 ± 10.5*  −20.0 Example 13  100 85.7 ± 14.2 75.6 ± 13.7  −12.5  300 73.4 ± 11.8 65.7 ± 13.8  −10.6 Example 18  100 73.9 ± 7.9  48.5 ± 4.9**  −34.3 1000 91.7 ± 13.8 79.3 ± 17.0  −13.5 Example 23  300 93.5 ± 7.0  86.4 ± 10.0  −7.6 1000 74.6 ± 10.2 61.9 ± 8.5**  −17.1 Example 42  300 83.1 ± 11.5 66.5 ± 9.9**  −20.0 1000 77.4 ± 5.4  70.3 ± 7.8   −9.2 Example 51  300 80.0 ± 6.2  73.7 ± 6.1   −7.9 1000 78.3 ± 6.7  67.9 ± 5.6*  −13.3 FLAVOXATE  300 89.2 ± 10.7 95.0 ± 10.9  +6.5 1000 90.4 ± 10.7 80.1 ± 11.1  −11.4 OXYBUTYNIN  100 95.2 ± 9.2  77.4 ± 10.3** −18.7  300 82.3 ± 8.7  50.5 ± 6.3**  −38.6 *= P < 0.05, **= P < 0.01 versus basal values; Student's t test for paired data

EXAMPLE 92

Radioreceptor Binding to 5-HT_(1A) and other different neurotransmitter binding sites.

A. Methods

Recombinant Human 5HT 1A Receptors

Genomic clone G-21 coding for the human 5-HT1A serotonergic receptor is stably transfected in a human cell line (HeLa). HeLa cells were grown as monolayers in Dulbecco's modified Eagle's medium (DMEM), supplemented with 10% fetal calf serum and gentamicin (100 mg/ml), 5% CO₂ at 37° C. Cells were detached from the growth flask at 95% confluence by a cell scraper and were lysed in ice-cold 5 mM Tris and 5 mM EDTA buffer (pH 7.4). Homogenates were centrifuged at 40000×g×20 min and pellets were resuspended in a small volume of ice-cold 5 mM Tris and 5 mM EDTA buffer (pH 7.4) and immediately frozen and stored at −70° C. until use. On the day of experiment, cell membranes were resuspended in binding buffer: 50 mM Tris HCl (pH 7.4), 2.5 mM MgCl2, 10 μM pargiline (Fargin et al., Nature 335, 358-360, 1988). Membranes were incubated in a final volume of 1 ml for 30 min at 30° C. with 0.2-1 nM [3H]8-OH-DPAT, in absence or presence of competing drugs; non-specific binding was determined in the presence of 10 μM 5-HT. The incubation was stopped by addition of ice-cold Tris-HCl buffer and rapid filtration through 0.2% polyethyleneimine pretreated Whatman GF/B or Schleicher & Schuell GF52 filters.

Native 5-HT_(2A) Serotoninergic Receptors and α₂-adrenoceptors (from aninmal tissues)

Binding studies on native α₂ adrenergic receptors (Diop L. et al, J. Neurochem. 41, 710-715, 1983), and 5-HT2A serotonergic receptors (Craig A. and Kenneth J., Life Sci. 38, 117-127, 1986) were carried out in membranes of rat cerebral cortex. Male Sprague Dawley rats (200-300 g, SD Harlan/Nossan, Italy) were killed by cervical dislocation and cerebral cortexes were excised and immediately frozen in liquid nitrogen and stored at −70° C. until use. Tissues were homogenized (2×20 sec) in 50 volumes of cold 50 mM Tris-HCl buffer pH 7.4, using a Polytron homogenizer (speed 7). Homogenates were centrifuged at 49000×g for 10 min, resuspended in 50 volumes of the same buffer, incubated at 37° C. for 15 min and centrifuged and resuspended twice more. The final pellets were suspended in 100 volumes of 50 mM Tris-HCl buffer pH 7.4, containing 10 μM pargiline and 0.1% ascorbic acid (a2 adrenergic receptors) or in 100 volumes of 50 mM Tris-HCl buffer pH 7.7 (5-HT2A serotonergic receptors). Membranes were incubated in a final volume of 1 ml for 30 min at 25° C. with 0.5-1.5 nM [3H]rauwolscine (a2-adrenergic receptors) or for 20 min at 37° C. with 0.7-1.3 nM [3H]ketanserin (5-HT2A receptors), in absence or presence of competing drugs. Non-specific binding was determined in the presence of 10 μM phentolamine (a2-adrenergic receptors) or 2 μM ketanserin (5-HT2A serotoninergic receptors). The incubation was stopped by addition of ice-cold 50 mM Tris-HCl buffer and rapid filtration through 0.2% polyethyleneimine pretreated Whatman GF/B or Schleicher & Schuell GF52 filters. The filters are then washed with ice-cold buffer and the radioactivity retained on the filters was counted by liquid scintillation spectrometry.

B. Results

The inhibition of specific binding of the radioligands by the tested drugs was analyzed to estimate the IC50 value by using the non-linear curve-fitting program Allfit (De Lean et al., Am. J. Physiol. 235, E97-E102, 1978). The IC50 value was converted to an affinity constant (Ki) by the equation of Cheng & Prusoff (Cheng, Y. C.; Prusoff, W. H. Biochem. Pharmacol. 22, 3099-3108, 1973).

The results shown in Table 3A demonstrate that compound A and the compound of Example 2 both have a very high affinity for 5-HT_(1A) receptors, but their binding profile is different. The compound of Example 2 was much more selective than compound A for the 5-HT_(1A) receptor versus the 5-HT_(2A) and the a2-adrenoceptors. All the other compounds of the invention tested (Table 3B) had high affinity for the 5-HT1A receptor.

TABLE 3B Binding affinity for the 5-HT_(1A) receptor Data are expressed as Ki (nM). Compound 5-HT_(1A) Ex. 3 10.28 Ex. 4 0.64 Ex. 5 14.85 Ex. 6 0.45 Ex. 7 3.82 Ex. 8 0.36 Ex. 10 17.23 Ex. 11 2.92 Ex. 12 4.77 Ex. 13 0.50 Ex 14 10.32 Ex 15 6.20 Ex. 16 2.9 Ex. 17 20.15 Ex. 18 0.60 Ex. 20 24.62 Ex. 21 2.72 Ex. 22 18.18 Ex. 23 0.14 Ex. 25 8.91 Ex. 26 2.69 Ex. 27 0.57 Ex. 28 18.78 Ex. 30 7.96 Ex. 32 19.36 Ex. 34 16.27 Ex. 35 8.00 Ex. 38 1.02 Ex. 39 2.65 Ex. 45 2.21 Ex. 46 6.05 Ex. 47 2.33 Ex. 48 0.46 Ex. 49 0.17 Ex. 50 1.16 Ex. 51 0.24 Ex. 52 34 Ex. 53 11.75 Ex. 55 10.78 Ex. 56 2.13 Ex. 57 0.74 Ex. 58 2.44 Ex. 65 18.62 Ex. 66 0.76 Ex. 67 4.76 Ex. 68 9.32 Ex. 69 0.32 Ex. 70 28.09 Ex. 71 15.48 Ex. 72 1.22 Ex. 73 21.23 Ex. 74 2.02 Ex. 76 0.69 Ex. 77 0.58 Ex. 83 1.31 Ex. 84 23.23 Ex. 88 1.03

Measurement of Pre- and Post-Synaptic 5-HT_(1A) Receptor Antagonist Activity

A. Methods

Antagonism of Hypothermia Induced by 8-OH-DPAT in Mice (Pre-synaptic Antagonism)

The antagonistic effect of the 5-HT_(1A) receptor antagonists of the invention on hypothermia induced by 8-OH-DPAT was evaluated by the method of Moser (Moser, Eur.J.Pharmacol., 193:165, 1991) with minor modifications as described below. Male CD-1 mice (28-38 g) obtained from Charles River (Italy) were housed in a climate-controlled room (temperature 22±2 C.; humidity 55±15%) and maintained on a 12 h light/dark cycle with free access to food and water. On the day of experiment, mice were placed singly in clear plastic boxes under the same ambient conditions. Body temperature was measured by the insertion of a temperature probe (Termist TM-S, LSI) into the rectum to a depth of 2 cm. Rectal temperature was measured immediately prior to intravenous injection of the test compound. All animals then received 8-OH-DPAT (0.5 mg/kg s.c.) and their temperature was measured 30 min later. For each animal, temperature changes were calculated with respect to pretreatment values and the mean values were calculated for each treatment group. A linear regression equation was used in order to evaluate ID₅₀ values, defined as the dose of antagonist needed to block 50% of the hypothermic effect induced by 0.5 mg/kg 8-OH-DPAT administered subcutaneously.

Inhibition of Forepaw Treading Induced by 8-OH-DPAT in Rats (Post-synaptic Antagonism).

The inhibitory effect of 5-HT_(1A) receptor antagonists on the forepaw treading induced in rats by subcutaneous injection of 8-OH-DPAT was evaluated by the method of Tricklebank (Tricklebank et al., Eur. J.Pharmacol., 117:15, 1985) with minor modifications as described below. Male Sprague-Dawley rats (150-175 g) obtained from Charles River (Italy), were housed in a climate-controlled room and maintained on a 12 h light/dark cycle with free access to food and water. On the day of experiment, rats were placed singly in clear plastic boxes. Rats were treated with reserpine, 1 mg/kg s.c., 18-24 h before the test to deplete intracellular stores of noradrenaline. For evaluation of antagonistic activity, compounds were i.v. administered 16 min before 8-OH-DPAT (1 mg/kg s.c.). Observation sessions of 30 s duration began 3 min after treatment with the agonist and were repeated every 3 min over a period of 15 min. The appearance of the forepaw treading symptom induced by postsynaptic stimulation of the 5HT_(1A) receptors was noted, and its intensity was scored using a ranked intensity scale in which: 0=absent, 1=equivocal, 2=present and 3=intense. Behavioral scores for each treated rat were accumulated over the time course (5 observation periods) and expressed as mean values of 8-10 rats. A linear regression equation was used in order to evaluate ID₅₀ values, defined as the dose of antagonist needed to block 50% of the forepaw treading intensity induced by 1 mg/kg 8-OH-DPAT administered subcutaneously.

B. Results

The results are shown in Table 4. These results demonstrate that compound of Example 2 exhibits significant pre-synaptic and post-synaptic 5-HT_(1A) receptor antagonist activity. Compound A, by contrast, proved at least 10 fold less active than compound of Example 2 in both models.

TABLE 4 Antagonistic activity for the pre- and post-synaptic 5-HT_(1A) receptor. Data are expressed as ID₅₀ in mg/kg. Pre-synaptic 5-HT_(1A) Post-synaptic 5-HT_(1A) Compound ID₅₀ ID₅₀ Compound A 221 350 Example 2 20 36 Example 13 — 82 Example 18 n.a. 84 Example 23 — 177 

What is claimed is:
 1. A compound of the formula

wherein R=hydrogen; R₁ is chosen from the group consisting of hydrogen and lower alkyl; R₂ is chosen from the group consisting of alkoxy, phenoxy, nitro, cyano, acyl, amino, acylamino, alkylsulphonylamino, alkoxycarbonyl, N-acylaminocarbonyl, N-alkylaminocarbonyl, N,N,-dialkylaminocarbonyl, aminocarbonyl, halo, trifluoromethyl or polyfluroalkoxy group; n=1 or 2; B is chosen from the group consisting of, optionally substituted aryl, optionally substituted bicyclic aryl group, optionally substituted 9-member bicyclic heteroaromatic containing one heteroatom, and an optionally substituted benzyl group, with the proviso that if B is aryl and is substituted by an alkoxy group, the alkoxy group must be at the two position; if R₁ is hydrogen and R₂ is a nitro group and n=1, then B cannot be a phenyl, 2 methoxyphenyl 4-chlorophenyl, 3 acetylphenyl, 3,4,5 trimethoxyphenyl, 2-chloro-4-methylphenyl or 2-pyridyl group; and if R is hydrogen and B is an optionally substituted phenyl ring, then R₂ cannot be acyl, acylamino, alkoxycarbonyl, N-acylaminocarbonyl, N-alkylamino carbonyl or N,N-dialkylamino carbonyl; or enantiomers, N-oxides, hydrates, and pharmaceutically acceptable salts thereof.
 2. A compound according to claim 1 wherein n=1.
 3. A compound according to claim 1 wherein B is optionally substituted phenyl.
 4. A compound according to claim 1 wherein B is indolyl.
 5. A compound selected from the group consisting of: 1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-phenoxyphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-iodophenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-aminocarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-nitrophenyl)-2-aminoethyl)-4-(2,5-dichlorobenzyl)piperazine; 1-[N-(2-methoxyphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-trifluoromethylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-[2-(2,2,2-trifluoroethoxy)phenyl]-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; [1-[N-(2-methoxycarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; [1-[N-(2-dimethylaminocarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; and [1-[N-(2-ethylaminocarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine.
 6. A pharmaceutical composition comprising a compound of claim 1 and a pharmaceutically acceptable diluent or carrier.
 7. A method for treating neuromuscular dysfunction of the lower urinary tract in a mammal in need of such treatment, said method comprising administering to said mammal an effective amount for treating said dysfunction a compound of the formula

wherein R=hydrogen; R₁ is chosen from the group consisting of hydrogen and lower alkyl; R₂ is chosen from the group consisting of alkoxy, phenoxy, nitro, cyano, acyl, amino, acylamino, alkylsulphonylamino, alkoxycarbonyl, N-acylaminocarbonyl, N-alkyklaminocarbonyl, N,N-dialkylaminocarbonyl, aminocarbonyl, halo, trifluoromethyl or polyfluroalkoxy group; n=1 or 2; B is chosen from the group consisting of optionally substituted aryl, optionally substituted bicyclic aryl group, optionally substituted 9-member heteroaromatic containing one heteroatom, and an optionally substituted benzyl group, with the proviso that if B is aryl and is substituted by an alkoxy group, the alkoxy group must be at the two position; and if R₁ is hydrogen and R₂ is a nitro group and n=1, then B cannot be a phenyl, 2 methoxyphenyl 4-chlorophenyl, 3 acetylphenyl, 3,4,5 trimethoxyphenyl , 2-chloro-4-methylphenyl or 2-pyridyl group; and if R and R₁ are hydrogen and B is an optionally substituted phenyl ring, then R₂ cannot be acyl, acylamino, alkoxycarbonyl, N-acylaminocarbonyl, N-alkylaminocarbonyl or N,N-dialkylaminocarbonyl; or enantiomers, N-oxides, hydrates, and pharmaceutically acceptable salts thereof.
 8. A method for treating neuromuscular dysfunction of the lower urinary tract in a mammal in need of such treatment, said method comprising administering to said mammal an effective amount for treating said dysfunction a compound, wherein said compound is chosen from the group consisting of 1-[N-(2-nitrophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-phenoxyphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-iodophenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-aminocarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl) piperazine; 1-[N-(2-nitrophenyl)-2-aminoethyl)-4-(2,5-dichlorobenzyl)piperazine; 1-[N-(2-methoxyphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-trifluoromethylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-[2-(2,2,2-trifluoroethoxy)phenyl]-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; [1-[N-(2-methoxycarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; [1-[N-(2-dimethylaminocarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; and [1-[N-(2-ethylaminocarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; or pharmaceutically acceptable salts thereof.
 9. The method of claim 7 or 8 wherein said compound is chosen from the group consisting of: 1-[N-(2-methoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-nitrophenyl)-2-aminopropyl]-4-(2-methoxyphenyl)piperazine; 1-[N-[2-(2,2,2-trifluoroethoxy)phenyl)]-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine; 1-[N-[2-(2,2,2-trifluoroethoxy)phenyl)]-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-trifluoromethoxy phenyl)piperazine; and 1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-bromo-5-methoxybenzyl)piperazine; or pharmaceutically acceptable salts thereof.
 10. The method of claim 7 wherein n=1.
 11. The method according to claim 7 wherein B is optionally substituted phenyl.
 12. The method according to claim 7 wherein B is indolyl.
 13. The method of claim 7 or 8, wherein said administration is effective for ameliorating at least one of urinary urgency, increased urinary frequency, incontinence, urine leakage, enuresis, dysuria, urinary hesitancy, and difficulty in bladder emptying in said mammal.
 14. A method for treating neuromuscular dysfunction of the lower urinary tract in a mammal in need of such treatment, said method comprising administering to said mammal an effective amount of a compound of claim 7 or 8 for ameliorating at least one of urinary urgency, increased urinary frequency, incontinence, urine leakage, enuresis, dysuria, urinary hesitancy, and difficulty in bladder emptying in said mammal.
 15. A method for treating neuromuscular dysfunction of the lower urinary tract in a mammal in need of such treatment, said method comprising administering to said mammal an effective amount of a compound of claim 8 or 9 for ameliorating at least one of urinary urgency, increased urinary frequency, incontinence, urine leakage, enuresis, dysuria, urinary hesitancy, and difficulty in bladder emptying in said mammal.
 16. The method of claim 7 or 8, wherein said administering is achieved using a route selected from the group consisting of oral, enteral, intravenous, intramuscular, subcutaneous, transmucosal, transdermal, and by-inhalation routes.
 17. The method of claim 16, wherein said compound is administered to said mammal in an amount of between about 0.01 and 25 mg/kg/day.
 18. The method of claim 17, wherein said amount is between about 0.2 and about 5 mg/kg/day.
 19. The method of claim 16, wherein the amount of said compound is between about 50 and 400 mg/day.
 20. The method of claim 19, wherein the amount of said compound is about 200 mg/day.
 21. The method of claim 7 or 8, wherein said administering is achieved using a route selected from the group consisting of oral and transdermal routes.
 22. The method of claim 7 or 8, wherein the amount of said compound is between about 0.1 and 10 mg/kg/day.
 23. The pharmaceutical composition of claim 6 which comprises at least one excipient selected from the group consisting of lubricants, plasticizers, colorants, absorption enhancers, and bactericides.
 24. A method for treating neuromuscular dysfunction of the lower urinary tract in a mammal in need of such treatment, said method comprising administering to said mammal an effective amount for treating said dysfunction a compound chosen from the group consisting of 1-[N-cyclohexylcarbonyl-N-(2-methanesulphonylaminophenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-methoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-benzyloxycarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-nitrophenyl)-N-(2-pyrazinecarbonyl)-2-aminoethyl)]-4-(4-indolyl)piperazine; 1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)-piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-amino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl-4-(4-acetylamino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-trifluoroacetylamino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-propoxycarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-(N-acetyl-N-cyclohexylcarbonyl)amino-2-methoxyphenyl]piperazine; 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-(bis-cyclohexylcarbonyl)amino-2-methoxyphenyl]piperazine; 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-cyclohexanecarbo-nylamino-2-methoxyphenyl)piperazine; 1-[N-(2-nitrophenyl)-N-(2-pyrimidinecarbonyl)-2-aminoethyl)]-4-(2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(2-methoxy-4-nitrophenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(4-amino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(4-acetylamino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl)]-4-(4-acetylamino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-trifluoromethoxyphenyl)piperazine; 1-[N-(2-nitrophenyl)-N-(5-thiazolylcarbonyl)-2-aminoethyl)]-4-(2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-bromo-5-methoxybenzyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-iodophenyl)-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-trifluoromethoxyphenyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-amino-2-methoxyphenyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-acetylamino-2-methoxyphenyl)piperazine; 1-[N-(2-acetylphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-bromo-5-methoxybenzyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(1-cyclohexylcarbonyl-4-indolyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-amino-2-cyanophenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-cyanophenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-methanesulphonylaminophenyl)-2-aminoethyl]-4-(4-indolyl)piperazine; and 1-[N-cyclohexylcarbonyl-N-(2-methoxyphenyl)-2-aminoethyl]-4-(1-cyclohexylcarbonyl-4-indolyl)piperazine; or pharmaceutically acceptable salts thereof.
 25. The method of claim 24, wherein said administration is effective for ameliorating at least one of urinary urgency, increased urinary frequency, incontinence, urine leakage, enuresis, dysuria, urinary hesitance, and difficulty in bladder emptying in said mammal.
 26. A method for treating neuromuscular dysfunction of the lower urinary tract in a mammal in need of such treatment, said method comprising administering to said mammal an effective amount of a compound of claim 24 for ameliorating at least one of urinary urgency, increased urinary frequency, incontinence, urine leakage, enuresis, dysuria, urinary hesitancy, and difficulty in bladder emptying in said mammal.
 27. The method of claim 24, wherein said administering is achieved using a route selected from the group consisting of oral, enteral, intravenous, intramuscular, subcutaneous, transmucosal, transdermal, and by-inhalation routes.
 28. The method of claim 27, wherein said compound is administered to said mammal in an amount of between about 0.01 and 25 mg/kg/day.
 29. The method of claim 27, wherein said amount is between about 0.2 and about 5 mg/kg/day.
 30. The method of claim 27, wherein the amount of said compound is between about 50 and 400 mg/day.
 31. The method of claim 30, wherein the amount of said compound is about 200 mg/day.
 32. The method of claim 24, wherein said administering is achieved using a route selected from the group consisting of oral and transdermal routes.
 33. The method of claim 37, wherein the amount of said compound is between about 0.1 and 10 mg/kg/day.
 34. A pharmaceutical composition comprising a compound of claim 24 and a pharmaceutically acceptable diluent or carrier.
 35. The pharmaceutical composition of claim 34, which comprises at least one excipient selected from the group consisting of lubricants, plasticizers, colorants, absorption enhancers, and bactericides.
 36. A compound of the formula

wherein R is a hydrogen atom, an alkylcarbonyl, a cycloalkylcarbonyl, a substituted cycloalkylcarbonyl or a monocyclic heteroarylcarbonyl group, n=1 or 2, R₁ is a hydrogen atom or a lower alkyl group, R₂ is an alkoxy, phenoxy, nitro, cyano, acyl, amino, acylamino, alkylsulphonylamino, alkoxycarbonyl, aminocarbonyl, N-alkylaminocarbonyl, N,N-dialkylaminocarbonyl, N-acylaminocarbonyl, halo, trifluoromethyl or polyfluoroalkoxy group, and B is a bicyclic heteroaromatic with the proviso that B is not a 9-member bicyclic heteroaromatic containing one heteroatom.
 37. A compound according to claim 36 wherein n=1.
 38. A compound according to claim 36 wherein B is a 10-member bicyclic heteroaromatic containing one heteroatom.
 39. A compound according to claim 36 wherein B is quinolyl.
 40. A pharmaceutical composition comprising a compound of claim 36 and a pharmaceutically acceptable diluent or carrier.
 41. A pharmaceutical composition comprising a compound of claim 37, 38 or 39 and a pharmaceutically acceptable diluent or carrier.
 42. The compound according to claim 36 1[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(8-quinolyl)piperazine or pharmaceutically acceptable salts thereof.
 43. A method for treating neuromuscular dysfunction of the lower urinary tract in a mammal in need of such treatment, said method comprising administering to said mammal an effective amount for treating said dysfunction a compound of the formula

wherein R is a hydrogen atom, an alkylcarbonyl, a cycloalkylcarbonyl, a substituted cycloalkylcarbonyl or a monocyclic heteroarylcarbonyl group, n=1 or 2; R₁ is a hydrogen atom or a lower alkyl group, R₂ is an alkoxy, phenoxy, nitro, cyano, acyl, amino, acylamino, alkylsulphonylamino, alkoxycarbonyl, aminocarbonyl, N-alkylaminocarbonyl, N,N-dialkylaminocarbonyl, N-acylaminocarbonyl, halo, trifluoromethyl or polyfluoroalkoxy group; and B is a bicyclic heteroaromatic with the proviso that B is not a 9-member bicyclic heteroaromatic containing one heteroatom.
 44. The method according to claim 43 wherein n=1.
 45. The method according to claim 43 wherein B is a 10-member bicyclic heteroaromatic containing one heteroatom.
 46. The method according to claim 43 wherein B is quinolyl.
 47. The method according to claim 41 wherein said compound is 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(8-quinolyl)piperazine.
 48. The method of claim 43, wherein said administration is effective for ameliorating at least one of urinary urgency, increased urinary frequency, incontinence, urine leakage, enuresis, dysuria, urinary hesitancy, and difficulty in bladder emptying in said mammal.
 49. A method for treating neuromuscular dysfunction of the lower urinary tract in a mammal in need of such treatment, said method comprising administering to said mammal an effective amount of the compound of claim 43 for ameliorating at least one of urinary urgency, increased urinary frequency, incontinence, urine leakage, enuresis, dysuria, urinary hesitancy, and difficulty in bladder emptying in said mammal.
 50. A method for treating neuromuscular dysfunction of the lower urinary tract in a mammal in need of such treatment, said method comprising administering to said mammal an effective amount of the compound of claim 44, 45 or 46 for ameliorating at least one of urinary urgency, increased urinary frequency, incontinence, urine leakage, enuresis, dysuria, urinary hesitancy, and difficulty in bladder emptying in said mammal.
 51. The method of claim 50, wherein said administering is achieved using a route selected from the group consisting of oral, enteral, intravenous, intramuscular, subcutaneous, transmucosal, transdermal, and by-inhalation routes.
 52. The method of claim 51, wherein said compound is administered to said mammal in an amount of between about 0.01 and 25 mg/kg/day.
 53. The method of claim 52, wherein said amount is between about 0.2 and about 5 mg/kg/day.
 54. The method of claim 51, wherein the amount of said compound is between about 50 and 400 mg/day.
 55. The method of claim 54, wherein the amount of said compound is about 200 mg/day.
 56. The method of claim 43, wherein said administering is achieved using a route selected from the group consisting of oral and transdermal routes.
 57. The method of claim 56, wherein the amount of said compound is between about 0.1 and 10 mg/kg/day.
 58. A pharmaceutical composition comprising, a compound of claim 42 and a pharmaceutically acceptable diluent or carrier.
 59. The pharmaceutical composition of claim 58 which comprises at least one excipient selected from the group consisting of lubricants, plasticizers, colorants, absorption enhancers, and bactericides.
 60. A compound chosen from the group consisting of 1-[N-cyclohexylcarbonyl-N-(2-methanesulphonylaminophenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-methoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-benzyloxycarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-nitrophenyl)-N-(2-pyrazinecarbonyl)-2-aminoethyl)]-4-(4-indolyl)piperazine; 1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-amino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-acetylamino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-trifluoroacetylamino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-propoxycarbonylphenyl)-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-(N-acetyl-N-cyclohexylcarbonyl)amino-2-methoxyphenyl]piperazine; 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-(bis-cyclohexylcarbonyl)amino-2-methoxyphenyl]piperazine; 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl]-4-[4-cyclohexanecarbonylamino-2-methoxyphenyl)piperazine; 1-[N-(2-nitrophenyl)-N-(2-pyrimidinecarbonyl)-2-aminoethyl)]-4-(2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(2-methoxy-4-nitrophenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(4-amino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl)]-4-(4-acetylamino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-[2-(2,2,2-trifluoroethoxyphenyl)]-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-nitrophenyl)-2-aminoethyl)]-4-(4-acetylamino-2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-trifluoromethoxyphenyl)piperazine; 1-[N-(2-nitrophenyl)-N-(5-thiazolylcarbonyl)-2-aminoethyl)]-4-(2-methoxyphenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]4-4-(2-bromo-5-methoxybenzyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-iodophenyl)-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-trifluoromethoxyphenyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-amino-2-methoxyphenyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-acetylamino-2-methoxyphenyl)piperazine; 1-[N-(2-acetylphenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-methoxyphenyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-cyanophenyl)-N-cyclohexylcarbonyl-2-aminoethyl]-4-(2-bromo-5-methoxybenzyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(1-cyclohexylcarbonyl-4-indolyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-amino-2-cyanophenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-cyanophenyl)piperazine; 1-[N-cyclohexylcarbonyl-N-(2-methanesulphonylaminophenyl)-2-aminoethyl]-4(4-indolyl)piperazine; and 1-[N-cyclohexylcarbonyl-N-(2-methoxyphenyl)-2-aminoethyl]-4-(1-cyclohexylcarbonyl-4-indolyl)piperazine; or pharmaceutically acceptable salt thereof.
 61. A pharmaceutical composition comprising a compound of claim 60 and a pharmaceutically acceptable diluent or carrier.
 62. A compound selected from the group consisting of: 1-[N-(2-methoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-nitrophenyl)-2-aminopropyl]-4-(2-methoxyphenyl)piperazine; 1-[N-[2-(2,2,2-trifluoroethoxy)phenyl)]-2-aminoethyl]-4-(2-methoxy-4-nitrophenyl)piperazine; 1-[N-[2-(2,2,2-trifluoroethoxy)phenyl)]-2-aminoethyl]-4-(4-indolyl)piperazine; 1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-trifluoromethoxyphenyl)piperazine; and 1-[N-(2-trifluoromethoxyphenyl)-2-aminoethyl]-4-(2-bromo-5-methoxybenzyl)piperazine; or pharmaceutically acceptable salts thereof. 